Miscellaneous Issues in Carving

These sections are concerned with advanced issues in stone carving, both technical and aesthetic. The sections are as follow:


When carving delicate areas such as limbs, fingers, and ears, carvers leave struts, i.e., bridges of stone, in place to support them until carving is complete. Bridges take advantage of stone's greatest strength, which is resistance to compression. Just as a huge stone can be split by a relatively trivial expansive force applied by wedges, appendages that stick out can be snapped off very easily, because of the leverage developed when force is applied from the side. Even a slender strut added behind the point where pressure might be applied adds tremendous strength. When planning bridging, rely only on the compressive strength of the stone, just as one would with a brick column in a building.

Nicolas Cordier, "St. Sebastian", marble. Struts left in place on raised left hand.34

Sculptors of other ages routinely left temporary bridging in place, not only for the duration of carving, but for shipment as well. The bridging was removed, and the attachments cleaned up, only after the piece was safely installed.

The picture above is a detail of St Sebastian, from the tomb of Lesa Deti in the Aldobrandini Chapel in Santa Maria sopra Minerva, Rome. It was installed, but left unfinished by Nicolas Cordier, apparently because of a dispute relating to payment. Several features are not quite complete, but most notably, bridging was left in place between the fingers of the upraised left hand. Note also the use of the branch to which the saint is bound as permanent bridging to support the cantilevered weight of the arm.

Daniel Chester French, "Asia", Limestone, the Custom House, New York, NY (detail). Strut left in place under left thumb.

The picture above shows a strut that was probably intentionally left in to support an otherwise fragile thumb in Daniel Chester French's allegorical group "Asia," which stands in front of the Custom House in New York.

Bridging should not be chiseled out, but should be sawn out carefully, with a fine toothed hacksaw. Chiseling it out would result in levering the supported piece, possibly breaking it off, and the use of a grinder to cut through the bridging would be risky. Binding of the grinder could result in the same kind of strong outward pressure as would be produced by chiseling, possibly enough to snap off the reinforced piece.

In classical sculpture, substantial bridging was frequently left in permanently, to support cantilevered masses which might eventually succumb to gravity even if they survived carving. Such bridging is usually found in positions where it would not be easily seen from vantage points available when the sculpture was in place. The marble Statue of a Wounded Warrior, a Roman marble copy (c. CE 138-181) of a Greek bronze (c.460-450 BCE), seen below shows the remains of permanent bridging that would probably have been obscured in the intended installation. This sculpture originally also had a bronze spear and shield attached.

Statue of a Wounded Warrior, Marble (detail), Metropolitan Museum of Art, NY

Permanent sculptural bridging is often disguised as an element of the composition. The ubiquitous tree stumps so often found in figure sculpture are usually structural. Drapery, weapons and other elements often perform a similar function. In the case of the warrior, the original bronze would not have required the additional support of either bridging or the tree trunk.


The eyes are the most obvious element of the human or animal figure for which properties such as color, gloss and wetness, that do not have a physical shape, are critical features. These features critical components of the expression of emotion and aliveness.

The Greeks painted or otherwise colored most sculptured marble (except for the flesh of women) but we know little of what they actually looked like, because few examples of polychromed Classical stone sculpture remain even partially intact. Examples of bronze sculpture exist with colored stone and glass inserts used for the irises and pupils. Painted-on details of lashes, eye color, and skin treatments of rubbed gold can still be detected. From these, and from chemical traces of pigments detected on ancient sculpture, it is inferred that smooth, blank eyes of classical Greek figures were almost certainly realistically painted.

The Roman tradition of sculpture, when not imitating the Greek, placed greater emphasis on naturalism and individual character. Roman figures, too, were often polychromed, but indications of the particulars of character and emotion, including those of the eyeballs are far more developed, especially in portrait sculpture. The Romans frequently carved the bulge of the cornea and indicated the depths of the pupil by drilling. They did not, however, often attempt to carve features of reflection and moisture, despite their intense concern with naturalism. These details are unnecessary when the stone surface is intended for painting.

The revival of ancient forms that characterized the Renaissance did not include polychromed surfaces for figures. All color had long since been lost from the then-known examples, as it had from almost all surviving classical buildings. The ancient traditions of sculpture were revived in a systematically distorted form, because they were largely divorced from the coloring and decoration that they were originally designed for. Thus, the Renaissance, Mannerist and Baroque masters increasingly added liveliness to sculpture of the face by developing techniques for "sculpting" shininess, wetness, color and other non-massive features.

The picture below illustrates an interesting example of the rendering of complex purely visual highlights sculpturally. Note the complexity of the reflection suggested by the carving in the iris, suggesting that the subject is indoors, in a darkened environment lit by multiple sources. The physical structure of the eye, the vivacity of the subject and his embedding in a complex world are deftly portrayed. The cornea is slightly recessed behind the sclera of the eyeball, faintly suggesting the arcus senilus characteristic of an aged subject. This effect is an almost graphical use of carving, because in life, the cornea bulges from the sclera. Note also that despite the representation of individual hairs in the eyebrows, the eyelashes are not directly rendered at all, but are suggested by the shadows cast by the excessively thick upper eyelid, which also contributes to the slightly rheumy, aged appearance of the eye. The effect in sculpture seen whole is of extreme realism, but the details taken individually are highly unrealistic. This level of visual complexity seldom appears before the Seventeenth Century, but sculptors even in the Classical world carved features, such as the iris, that have no existence in pure form, and the practice was common in the Renassance, even among purists like Michelangelo.

Christophe-Veyrier, Bust of Marquis Jean Deydé, detail, 168435.

The handling of the eyes in the Bernini bust of Scipione Borghese, below is also interesting. The double ring incised around the iris does not actually exist in the human eye, but combined with the depressed and roughened surface of the iris, which swallows light, making it seem to be dark a distance, and the raised stone gleam at the level where the cornea would be, it adds to the strong impression of the clarity of the eye. As in the Christophe-Veyrier bust, the eyelashes are not represented directly, but the thickened eyelid produces a shadow that gives the illusion of eyelashes. On the left we see how these small effects come together to make the image appear to be startlingy alive when seen at a more natural viewing distance. The artist has literally sculpted light, both in the eyes and in the skin.


The key to carving realistic flesh, particularly where flesh touches flesh, is making the wrapping, folding and dimpling of the skin believable. Skin, together with the attached fat behind it, has thickness--when it folds or creases outwardly, there is a minimum radius to the curve of the surface that implies this thickness; the smaller the radius, the thinner the implied skin. Inward folds don't have to wrap around a layer of fat, so the radius of curvature can be tighter.

The radius of the minimum curve tells much about the subjects age for a given location of the skin on the body. Toddlers have a thick layer of fat almost everywhere, so the radius is large. There can be no tight curves, so everything is smooth and plump; you can't really pinch a fold of toddler's skin. The eye is very good at sensing structures wrapped in skin and the visual correctness of the way the skin clings to the substructures. Except in small children, female skin retains a thicker layer of fat than male skin of similar age.

Thus, sculptors control the appearance of age by manipulating the minimum curvature of the surface of the skin. For adult men and women, skin is thinner on the face and hands, with older the person, the skin in these areas becomes almost paper-thin, especially on the hands. Wherever subcutaneous features of any kind need to be indicated, the maximum curvature of the skin determines how much detail can be seen on the surface. This is why the hands and the neck are said never to lie about age--these areas of the body contain a great deal of subcutaneous detail and they lose fat early.

Where a crease ends, the skin dimples up slightly in the same characteristic radius to take up the slack. The curvature of skin may always be less than the critical radius, but it must never be greater, or it won't look right. The critical radius varies from place to place on a given body, but it only changes abruptly in a few places, such as around the eyes and to some degree, the neck and hands, especially in older people.

Older people's skin loosens, in addition to having less subcutaneous fat. Loose skin is a reliable visual indicator of age--young people never have it. Face lifts tend look increasingly unnatural as the subject ages, because they remedy the looseness of the skin but don't replace the fat. Without enough fat, the taut skin begins to look unnatural. The same holds true for sculpture--the looseness of the skin and the implied thickness must be in sync.

Whatever the surface features of flesh, one of the most effective ways to model the subtle surface is with square-cut push chisels, as described in the section on push chisels. These tools permit the most delicate modulation of the surface without the need to allow for a margin for smoothing.

There are a number of ways to deal with the finish on flesh. Ancient works tend to have a flat, opaque, matte finish because the marble was usually uniformly bruised across the entire surface. They rarely show fine detail, although work in the Roman style, as opposed to Roman work imitating Greek, often has wrinkles and facial blemishes, but not minute detail.

Neoclassical works are often finished quite smoothly, but the sculptors scrupulously avoided bruising the stone because they were not to be painted.

Later Nineteenth Century works often have a more complex finish, by which the skin is given a richness through carful modulation of surface scratching. In many pieces, rasp marks and the marks of relatively coarse grinding with stones are not completely obliterated before the surface is ground with fine abrasives. This gives a rich, deeper look to skin, because of the slight surface sparkle, the white at the bottom of the scratches, and the scattering of light below the surface caused by the scratching. This is described more fully in the abrasives section. It is not a universally used technique, and it works better on some kinds of marble than on others.

Bernini's handling of flesh in the portrait of Scipione Borghese, seen below. is a fine case of directly representing the fine texture of the skin. Notice on the right, the rendition of the pores on the nose, the very fine wrinkles in the cheeks, and the slight creasing of the skin just below where the jaw meets the neck. These features are an order of magnitude or more smaller than the smallest directly carved features, such as the bunched skin and wrinkles around the eyes.

The finest wrinkling appears to have been achieved by finishing over rasp marks with a much finer abrasives. The creases in the sking of the neck seem to incised one by one below a more finely smoothed surface, and then the surfaces ground smoother.

The appearance of pores seems to have been produced by lightly finishing a surface that has been pre-textured, perhaps by a light impact with some kind of grainy stone. (Another way to achieve this kind of texture is to tap the marble with the bunched bristles of a wire brush. The impact of the tiny wire points scours out the softer material between crystals, leaving a stippled but smooth surface.) The impression of all of these textures is heightened by contrast with the glossy surfaces of the cardinal's satin vestment.

Portrait of Cardinal Scipione Borghese 1632, Gianlorenzo Bernini, Galleria Borghese, Rome

Multiple Pieces

Historically, many sculptors have been horrified by the idea of constructing a statue from more than one piece of stone. Like indirect carving, it seems to go against the essential nature of the stone. Yet the ancients did it routinely for arms and legs, and the practice has frequently been used for large pieces and the Romans sometimes even joined marble heads to wooden bodies draped in real cloth robes. Large reliefs were frequently carved as separate panels.

The key to success seems to be either very clever or very blatant. Large outdoor pieces are often made of blocks stacked together with no attempt to hide the seams. This seems to work best with rougher stones such as limestone.

Bernini sometimes used multiple pieces where a single piece of stone would be too large or unwieldy. He usually relied upon concealing the seams behind overlapping drapery or other features. One consideration is that multiple pieces cannot be carved as if they were one piece, because of the way the stone breaks across the edges. You cannot chisel continuously across a break, even if it's a hairline; you must always chisel into any edge. It is necessary to plan in advance for assembly too--points for lifting must be allowed for, and connecting pins should be in place before carving starts.

The Drill

The drill is used both as a marking tool, to project reference points into the block, and as a carving tool in its own right. While drilling is indispensable for deep or narrow cuts, round holes in a finished piece can be visually disturbing, particularly if they are repeated in similar size. As a carving tool, the drill has often been used with unhappy results to render curls in hair. The pictures below shows the undisguised use of the drill in the hair of Flora, by Pietro Bernini, in the execution of which he was assisted by his eighteen year old son, Gian Lorenzo Bernini. The younger Bernini's A Faun Teased by Children, seen below carved the same year, shows similar exposed drill marks. Perfectly round holes or fractions of cylinders tend to catch the eye very easily, giving carving a carving a riddled appearance when used to excess.

Pietro Bernini, Flora, detail, 1616, Metropolitan Museum of Art, New York, detail.
Gian Lorenzo Bernini, A Faun Teased by Children, detail, 1616-1617 Metropolitan Museum of Art, New York, Marble, H. 52 in.

The pictures below shows both the disguised and undisguised use of the drill. A large number of uniform-sized holes of approximately a quarter-inch in diameter appear as black circular dots, sometimes in the center of curls, and sometimes between curls. The curls themselves are carved as helixes around somewhat larger drilled holes, which have been disguised with varying degrees of success. Note particularly that the second curl to the right of the eye, the next curl further to the right, and the curl directly above it were all clearly carved around holes drilled with the same drill, the diameter being approximately three-eights of an inch.

Bernardino Cametti, Bust of Giovanni Andrea, detail, 1725 Metropolitan Museum of Art, New York, Marble

Particular care must be used when the drill is used as a rough carving tool, to honeycomb out a deep cut into a narrow space. Subsequent use of the chisel can develop a great deal of force against the walls, and can split a large mass of stone easily. With modern tools, it is often better to drill a line of holes with a small amount of stone separating them, then clean out with a flexible shaft grinder, or similar tool. Prior to the invention of electric hand tools, this was usually done with a running drill.

Indirect Carving

In many art media, for example, in oil painting, especially in the modern era, the creative act and the execution of the finished work are essentially the same thing. Regardless of the amount of planning, the placement of the elements is still being worked out and refined on the canvas until well into the process, and even after the painting has reached a point where the location and shapes of the major elements can no longer be changed signficantly, color, additional details, light and shadow, etc, continue to evolve until the painting is completed. The painting emerges from the manual process of the artist painting36. This is not true for all media, of course. At the other extreme, composers, and architects create only precise specifications for work that will almost always be entirely executed by others.

Many sculptors, especially within living memory, have ardently believed that an artist should create directly in stone, as a painter does with paint; that the sculpture must emerge from a personal, physical struggle with the medium. Such a sculptor may work from a maquette, as a painter works from a sketch, but the true creative act extends throughout the carving.

At the other end of the spectrum are sculptors who consider the pure form itself primary, and the fact that it is expressed in stone, a secondary issue, or even entirely irrelevant. These artists typically work in wax or clay, fully defining the form to be carved, in detail, usually full size, and then copy, or have the model copied, precisely in stone, with the aid of mechanical measuring devices.

Michelangelo, who dominated High Renaissance sculpture, and is probably the most admired sculptor in history, worked exclusively directly, but Antonio Canova, nearly as promininet in the Neoclassical world as Michelangelo had been in his time, almost always worked in clay, and then, working with assistants, copied the a plaster casting into stone using mechanical measuring devices. Canova was not unusual in this respect. Extensive use of copying machinery and assistants was the rule in the early Nineteenth century, and in the later Nineteenth Century, the majority of the most prominent sculptors did not care at all about direct carving, and handed off much, often all, of the carving to assistants, or to outside contractors. Many sculptors, including Rodin, for instance, deferred even the decision as to whether a piece would be executed in stone or in bronze until a purchaser made his or her wishes known, and in fact often produced the same piece in both media. Working in clay was overwhelmingly the rule, not the exception in the Nineteenth Century37 with only a few notable exceptions. As far back as the Renaissance, and perhaps further, sculptors and critics have divided into two camps on this issue, but at the heart of it is always the question of where the creative act occurs.

Direct vs. Indirect

At the lowest level, chiseling away stone is the same mechanical process for any kind of composition, but at a higher level, there is a fundamental technical difference between the carving of the relatively monolithic sculpture of early Classical Greece, or Modernism, and the carving of the more complex, fluid compositions of the Hellenistic period, the Late Renaissance, the Baroque, and subsequent periods. The difference is in how, and at what point in the process, the final form is determined.

The process of carving a monolithic form is like peeling layers from an onion; the surface shrinks towards the center, as layers of stone are removed. After the crudest roughing-out, the shrinkage tends to be fairly even. For such work, it is natural to carve from all sides, with the momentary state of the carving serving as an evolving frame of reference for judging what to remove next. For this reason, direct carving, like painting, both requires and rewards a constant focus by the artist on the state of the entire piece throughout the process. This kind of direct carving has been the default choice for most sculptors in the Twentieth and Twenty-First Centuries.

For at least two reasons, however, it is not generally practical to carve complex figurative compositions in this way. The less interesting, but still compelling, reason is that complex pieces require a great deal more work, and indirect carving allows the uniquely skilled (and/or persuasive) artist to off-load much of the carving to people with more ordinary skills.

The less obvious reason is that the conceptual difficulty of direct carving increases out of proportion to the complexity of the composition. In the onion model of carving a single mass, points on the surface of a mass move only inward, toward the center of the mass, which tends to stay in a more or less fixed location. But if a more complex sculpture composed of multiple masses is approached in the same way, then each of the major masses is a separate onion. A point on the surface of a given mass will move steadily closer to the center of that mass as layers are peeled away, but it will simultaneously be moving in any number of different directions with respect to the other masses. For example, pairs of points on two inward-facing surfaces will move away from each other while pairs of points on outward-facing surfaces of the same two masses will move towards each other. Roughly speaking, if the composition looks right in a rough stage, the masses will be much too far apart in more finished stages. Complex compositions invert the concerns of the sculptor: if two masses are to be in contact, the final polished surface of the point of contact is the first, not the last, thing that must be established, or the two masses will move apart as they are finished. The web of constraints that multiple elements put on the locations of the masses to each others force the first concern of the carver to be with the location of finished surfaces, rather than the volumes.

It is the need to work out the precise relationships of interacting masses, not the copying per-se, that makes complex compositions in stone qualitatively different from monolithic compositions. The use of clay to work everything out in advance is sometimes treated almost as a moral or ethical issue, as if the artist who works in clay were somehow cheating. But the requirement for precise pre-planning of complex work is actually inherent, and can only be avoided by not making complex compositions. Even if a hypothetical sculptor had the superhuman ability to imagine all of the finished surfaces of a piece within the block perfectly , and cut down to those precise points free-hand, it would only simulate direct carving--the compositional decisions would still have been made in advance, and could not be said to evolve in stone in the way that an expressionist or abstract painting or drawing does on a two dimensional surface.

This is why for the complex compositions of the generations that followed Michelangelo, the use of precise clay models became overwhelmingly the rule, and the separation of the the central creative act from the actual carving became more commonplace, making stone carving more like working in bronze.

The overwhelming movement of art towards expressionism, primitivism, and abstraction in early Twentieth Century, eliminated the tradition of complex figurative compositions, making direct carving once again the more natural way to carve, and other than a few schools, such as École des Beaux-Arts in Paris, that continued to emphasise classical techniques, the direct approach to stone has overwhelmingly dominated the practice and teaching of sculpture in stone since Modernism.

The practice of carving front to back arises naturally when complex compositions are to be carved without mechanical copying. Because the final relative locations of the masses are fixed by the points where the masses touch each other, or interact closely, it makes sense to identify such points, which are by definition on the finished surface, at the outset. When working from front to back, if the figures are drawn carefully on the front and sides of the block, the furthest-front elements to be located fairly precisely, and carved first, giving a set of precise locations of finished surfaces that will not be lost as the carving progresses, wich can be used along with the remaining drawings on the side, to locate further points on the sufrace until far into the process.

This process thus occupies a middle ground on the way to fully indirect carving, in that it relies upon finding and fixing the precise placement of points on the finished surface at the beginning. Dealing with finished surfaces at the outset inherently de-emphasizes the direct carver's use of the current state of the masses as a reference for the carving next state, but less so than the direct transfer of points a model to all sides of the piece.

Vasari[Vasari 07-2], in reference to Michelangelo, does not make this explicit, but does mention another interesting reason for abandoning the direct carver's practice of working from all around. It is not unusual for flaws and inclusions to be hidden within a perfect-seeming block. To paraphrase Vasari, working from front to back keeps one's options for recovery from an unforeseen problem open, for as long as possible. Yet another practical advantage not mentioned by Vasari, is that for complex carvings, say, the snakes and extended appendages in the The Laocoön group, the uncarved background serves as scaffolding for the pieces that would otherwise be unsupported.

For modern carvers, each approach has its aesthetic strengths. Direct carving is at its most practical with one artist per object because the essential creative act is concurrent with the execution. The results tend to express a stone-like solidity, at least in part because the design decisions are made on a pay-as-you-go basis, and the emergence of the carving from the process is consistent with relatively less formal modernism.

For better or for worse, indirect carving conduces to a very different sensibility in several ways. Most obviously, creating the composition in clay allows the artist to make carvings of a complexity that would be extraordinarily difficult for a direct carver, and to experiment with compositions, make changes, and even start over from scratch, at relatively little cost.

Indirect carving also also profoundly changes the economics of making sculpture. The output of direct carvers is severely limited, as is their ability to produce work quickly, because the creative act, for which the nominal artist is essential, takes as long as the carving. The division of labor made possible by indirect carving allows a successful artist to produce an enormously larger body of work. Moreover, it is not just the making of original work that is facilitated--the same techniques allow the production of multiples, diffusing the artist's work to a much larger audience, further fueling demand. For a sculptor, the use of indirect techniques thus becomes both the consequence of, and the path to, celebrity. Historically, this is not a minor effect--Bernini, Canova, Rodin, and many others who were the preeminent sculptors of their time, headed studios that employed numerous assistants apprentices, and collaborators, and produced numerous copies and versions of their most famous work.

Despite the intensity of our modern passion for direct carving, historically, all the way back to ancient Greece, it has been more typical for sculptors to regard the abstract form as the primary thing, and whether it is expressed in stone or bronze, as essentially incidental.

The Classical World

This is a placeholder for material extracted from Blumel, Adam, and Richter.

The Renaissance and Baroque

Michelangelo Buonarroti (1475-1546), the quintessential sculptor's sculptor, was famously of the direct carving camp. He planned meticulously, but usually carved with only a small bozzetto as his only guide38. It is no coincidence that Michelangelo was obsessed with both stone carving and Neoplatonism, which was then revolutionizing the intellectual life of the Renaissance. Platonism is concerned with the division between the reality of Forms, and the concrete world we are able to experience39. The art of the sculptor, as understood in the Renaissance40, was the expression of pure form in the most tangible of media.

Michelangelo remains fascinating to every generation, in part because his search for the Forms behind reality is so explicit in his mature carving. His David, and the glittering surfaces of the Vatican Pietá are the work of his youth (both were completed before he was thirty) but his more mature work was quite different: craggier, frequently showing tool marks, especially the claw chisel, and often unfinished. It is deeply satisfying, especially to the modern eye, to be able to see the imprint of his struggle in the unfinished work. His last work, the Rondanini Pietá, which he continued to work on during the last week of his life, at the age of 88, is the ultimate expression of this. The piece is hacked from the ruins of an earlier, nearly finished version, leaving unfinished an attenuated, almost ghostly version of Mary holding the dead Jesus upright.

Both Michelangelo and Donatello worked primarily from small bozzetti, eschewing indirect techniques, but even in their day, this was was exceptional, and in Michelangelo's case, somewhat misleading.

Michelangelo carved without aid of measurement, but he famously had an uncanny ability to imagine shapes in space41, and his approach to the block remains, to this day, highly unusual among direct carvers, although it was advocated by Hildebrand for somewhat different reasons (see below). Working from front to back, Michelangelo often executed the carving fully, as he proceeded through the block, so that portions of the front were finished while much of the piece remained buried under untouched stone. Vasari describes this process, which he viewed first hand in his Lives [Vasari 07-2]. As detailed above, this is the direct carvers way of solving the problem of locating interrelating masses in space without direct measurument, and in this, Michelangelo was re-creating a process that had been used extensively by Hellenistic carvers.

It is interesting that in his latest, and in some ways most passionate work, his process least resembles these Hellenistic-era practices, and becomes almost expressionistically direct, as in the Rondanini Pietá,cited above.

More typically, Renaissance sculptors favored full sized models copied with the aid of manual measurement, although they did not use precise mechanical pointing that came into use in more modern times.

Vasari describes the ordinary procedure for Renaissance sculptors in detail [Vasari 07-2], pp. 48. A Renaissance sculpture typically started as a small bozzetto, which was then enlarged to a full-size figure in clay reinforced with horse-hair or other fiber. The clay figure was first modelled naked, and the drapery applied on top, not as clay, but as real cloth, soaked in clay slip so that it would be rigid when dry. The full size figure was allowed to dry (the reason why fiber reinforcement was necessary,) then copied in stone using carpenter's squares to establish corresponding points between clay and stone42. The use of carpenters squares falls short of true indirect carving, and is more akin to what a painter does in visually measuring with his or her thumb.

Still others, for instance Gian Lorenzo Bernini (1598-1680), the premier sculptor of the Baroque period and the quintessential virtuoso, gloried in their own craftsmanship, but did not scruple to use indirect carving when the scale, complexity, market demand, or issues of positioning demanded it. Bernini's works are so numerous, and on such a scale, that the attribution of work to him can be a judgment call; works attributed to Bernini may be entirely by his hand, executed with the help of other master sculptors, or merely designed and supervised by him43. While Bernini himself seems not to have personally carved indirectly, and executed many of his most famous works single-handely, much of his work used a different kind of indirect carving. He often made precise, full sized models, and handed off large amounts of the work to assistants who, working from his model, blocked out the sculpture for him. He also often hired specialists to execute decorative detail, such as foliage and clothing.

The Neoclassical Era

Antonio Canova (1757-1822), like Michelangelo and Bernini before him, was a true virtuoso carver, who dominated sculpture in his time. He was among the most famous and highly regarded artists of his time, without a doubt the most famous sculptor, and among the first artists to be truly a celebrity in the modern sense of the word. The epitome of the Neoclassical style, Canova's work is cold by modern standards, and easier to admire than to love, but his mastery of the medium is unquestioned. For a number of reasons, a great deal is known about how Canova worked. Not only have many of his plaster models been preserved, but his studio was open to the public, and numerous description of the master and his assistants at work have survived, along with detailed drawings of the process. In addition to this, his friend and colleague, the sculptor Johann Gottfried Schadow, who's work is very similar to Canova's, wrote a paper, "The Sculptor's Studio" in 1802, that detailed his working processes, and how several people worked together to execute a large piece.

Canova worked predominately indirectly, and made extensive use of assistants as his growing fame created a demand for his work that far exceedeed what any sculptor could produce alone. In addition to a huge output of new work, many of his most famous works were executed repeatedly, including Psyche Revived by Cupid's Kiss, Perseus with the Head of Medusa, and The Three Graces.

Hugh Honor's monograph on Canova's technique, Canova's Studio Practice, [Honor 72], describes how Canova's pieces were executed. The master himself conceived the designs, did the drawings, and personally executed the originals in clay. These originals were cast in plaster, and numerous small iron pins were inserted to mark the points to be transferred into the stone block during the copying process see the image below

The actual transfer was done using both copying frames and calipers. Identical frames were erected above the model and the block to be carved, and a plumb line was lowered from the copying frame above the model to determine the precise location in space of a specific pin on the model. The horizontal position of the point was given by the point of attachment of the line to the copying frame, and the vertical location was given by the length of the plumb line. The marble below the corresponding point on the frame mounted above the block was then carved away until the plumb bob just reached the surface. The precise point was then marked, and the carvers moved on to the next point.

The monograph gives a detailed acount of the creation of the three figures for the tomb of Pope Clement XIV, seen below,

Canova,"Tomb of Clement XIV", Marble, 1792, Basilica di San Pietro, Vatican.

including how long each portion of the work took and how many workers were required. Canova spent approximately four months working on the clay models. Using three assistants, the carving of the figure of the Pope required 100 days of Canova's time, of which 45 were spent on the face and hands, while his assistants worked 192, 99, and 17 days on the the same piece.

The photograph below shows a detail of one of Canova's plaster originals with the iron pins marking points to be transferred into the marble block. Note that the tip of the pin is the point transferred, not the base, in order to leave a layer of stone for the final carving.

Detail for Canova model for Psyche Revived by Cupid's Kiss,plaster, 1794, Metropolitan Museum of Art, New York. Note the iron pins.

Honor's monograph is not explicit on the issue, and the period illustrations are not clear, but as only points that are on top surfaces can be reached with a plumb bob, the calipers were undoubtedly used to locate points on the surfaces that could not be reached in this way. See the section on the use of calipers for details on how this is done.

Canova was a perfectionist regarding the finished surfaces, and apparently did the final carving and smoothing himself by candlelight, in order to control the direction of illumination, for a better understanding of the surfaces.

Critics have made much of Canova's use of indirection, with some claiming he did almost none of his own work. Honor's monograph convincingly debunks this view. Canova was apparently highly active in all phases of carving in his earlier career, but as he got older, and the demands on his time increased, the proportion of his own contribution in time to to each piece decreased.

The 19th and 20th Centuries

Adolph von Hildebrand's44 1893 The Problem of Form, though now little read, and to many modern readers, unreadable, was one of the most influential works of criticism relating to sculpture ever written, influencing generations of critics and sculptors who followed, even across the divide of the Modernist revolution. His own work had more in common with the coolness of the Neoclassicists of the previous generation than with the lushness favored by his contemporaries, but his true aim was to revive the serene, monolithic spirit of the sculpture of the Age of Pericles. Compared to Hildebrand's ideal, Neoclassicism seems almost froufrou.

It is a book about much more than sculpture, and is one of the first attempts to unify aesthetics, and psychology, and to show why the true arts are not imitative, but architectonic, constructing the aesthetic experience out the combination of sense and mind. The arguments are all directed toward the final chapter, in which the author, an ardent admirer of Michelangelo, makes the makes the case that the achievements of Classical sculpture could only be emulated by an artist who carries direct carving to an extreme.

While Hildebrand's passion for direct carving has remained the dominant orthodoxy ever since, a closer examination of his reasoning leads one to suspects that the book was more widly admired than read. Hildebrand believed that the human eye can only understand form as a series of two dimensional layers at increasing distances from the viewer, and that sculpture in the Classical world had developed from drawing (i.e., a single layer) by way of relief carving. In Hildebrand's view, the true nature of sculpture is an extension of the relief, even when in the round, and that like relief, it should be designed for a frontal view, and executed, literally, from the front, as Michelangelo had worked, layer by layer. The completed work emerges from the block, but the essence of the block continues to exist, and to be expressed, in the completed sculpture. He regarded the progression of sculpture since Michelangelo towards complex compositions designed in clay, to be seen from every angle, as antithetical to the Classical spirit, and believed that Michelangelo's ideosyncratic practice of carving from front to back was of critical importance45 in emulating the spirit of Classical Greece.

Ironically, Hildebrand's contemporary, Auguste Rodin (1840-1917), who is generally acknowledged to be the greatest sculptor of his own time or since, is one of the artists of the late Nineteenth and Twentieth Centuries who cared least about drawing distinctions between modeling and carving. Profoundly non-intellectual, Rodin certainly could carve, but he was a dedicated modeler, who almost always worked in clay or wax. Just as he would leave bronze casting to specialists, he typically left the execution of his work in stone to highly skilled assistants, albeit, assistants working in his studio, under supervision.

Like the work of Michelangelo, Rodin's stone sculpture often non-finito, and features visible tool marks and raw stone, but both are done in a contrived and essentially decorative way. The marks are are usually unrelated to the origin of the forms themselves, which were fully worked out in clay in advance, and the uncarved sections of stone are planned from the start.

Rodin loved clay, but was almost indifferent to the final medium the piece would be executed in, and sometimes had plaster originals executed both in bronze and in stone. The Kiss, one of his most exquisite works in marble, was originally intended for casting in bronze, and was also executed in plaster and terracotta before it was first carved in stone for exhibition in the Salon de la Societe Nationale des Beaux-Arts in 1898. The piece was subsequently carved in multiple versions, in several sizes, and cast repeatedly in bronze, both with and without the permission of the artist.

Even Henry Moore, arch-Modernist of the generation following Rodin, and devotee of direct carving for a quarter century, shifted to indirect carving in the 1950's, when demand for his work, and increases in the scale at which he wanted to work, made carving it all himself infeasible. This was not a case of a deep-dyed direct carver resorting to indirect carving for massive pieces--Moore became a true modeler, and started producing work in both stone and bronze, eventually coming to regard clay as merely a faster way to get the same ideas out. See Lives of The Great 20th Century Artists[Lucy-Smith].

The contest between direct and indirect is never on a level field, because an aesthetic commitment to direct carving is self limiting--an artist can carve but so much stone in one lifetime, and few artists are physically capable of executing a large piece unaided in a reasonable amount of time. Whatever its aesthetic merits, indirect techniques multiply the productivity of an artist almost without limit, and therefore have historically tended to come to relative prominence whenever demand is great.

Naturalism and Verisimilitude

Notwithstanding the persistent romanticization of the ancient Greeks that began in the Renaissance, since Michelangelo's time, there have been countless virtuoso carvers who could shape stone as skillfully as any carver of the Classical world.

The paradox of stone sculpture is that for the great sculptors, the actual carving, per se, has never been the hard part. As pure craft, carving can be learned, like stone masonry (a branch of which sculpture was considered to be, prior to the Renaissance) and a skilled carver, given a model to work from, can reproduce any form that is consistent with the properties of the stone. What ultimately makes sculpture an art, rather than one of the building trades, is the ability of the artist to comprehend and define the pure form. Some artists have chosen to define that form directly in stone, but far more have worked in clay, and in either case, it is impossible to distinguish a high quality copy from an original by the artist's hand.

Even a glance at figurative carving of the Seventeenth Century makes it clear that it has been a very long time since there has been anywhere farther to go in terms of the mechanics of carving; certainly, sculptors since Bernini could make stone do anything that stone can do. Yet, throughout history, naturalism--representing particular, individual people in a lifelike way--has rarely been a primary goal of sculptors. Rather, naturalism has traditionally been subordinated to the creation of imagery that would not be overpowered by the primal force of the medium.

In the Nineteenth Century, Neoclassicists such as Canova and Schadow carried stylization of faces to an extreme. The image of Perseus on the far left of the image below is a typical example, but all the way back to the Renaissance, we see a limit to the degree to which sculptors in stone pursued verisimilitude as a goal. Michelangelo's David seems breathtakingly vivid and alive, but the artist's rendering of David's body is quite exaggerated, and the face, as seen on the left below is not remotely naturalistic--a living person who actually had such a face would be terrifying. His Vatican Pietá is similar: Mary would be a bizarre looking woman indeed, with a tiny head46 enormously wide shoulders, and 65 inch hips, with about a foot of space between her thighs. Likewise the work of Bernini: St. Teresa, also shown below, is a powerful image which seems almost to breathe with life, but the rendering is actually highly artificial--no living woman ever looked like St. Theresa. This kind of artificiality is not for want of skill--all three sculptors were masters of the craft who could carve anything they wanted to. Even the sculptors of the Eighteenth Century who carried naturalism the furthest, retained a stylistic artificiality that imposed a distance between the representation and the human form.

There is a conflicting critical literature on why this is so consistently true, and undoubtedly the reasons vary to some extent from era to era, but one key reason is that verisimilitude is only one of the problems facing a sculptor. A common thread running through much of the literature on sculpture is that a figurative sculpture has multiple natures that the artist must reconcile. A statue is an image of something, but it is also an object itself that takes up physical space, and is made of a material which has its own powerful presence in a way that a canvas does not. Stone is almost the opposite of the flesh that it portrays: cold, and hard, indifferent to the time. Its association with architecture and its permanence make it a natural attribute of power; emperors do not declare their status with watercolors. Reconciling the image with the density and physical presence of the material is a fundamental problem that sculptors have always had to deal with.

Michelangelo's David (detail), 1504, Gian Lorenzo Bernini's Extacy of St. Teresa(detail),1652, Antonio Canova's Perseus (detail), 1801

In the Nineteenth Century, starting with a few sculptors who are nominally Neoclassicists, such as Houdon and Chantrey, a new kind of naturalism began to appear that was very different from traditional carving--a handling of stone that produced not just an image, but the illusion of life. Aesthetically, this is almost a magic trick, like a perfumer compounding a delicate scent from musk.

This kind of naturalism in three dimensions is a mysterious thing. Superficially, it appears to be like photography, but it is not, for no true three-dimensional analogy of photography exists for living things. The mental machinery for interpreting the two dimensional projection of the world on our retina allows us to interpret photographs and paintings even though they are in no way realistic. Little boys, like the one shown below do not have heads that are nearly as wide as their shoulders, yet the image is perfectly convincing. The closest thing to a photograph in three dimensions is a plaster life casting, yet though a casting may reproduce the shape of human features perfectly, the casting invariably looks physically shrunken and dead, and painting the plaster does not diminish the effect. For one thing, there is no such thing as "flesh tone" paint, because skin does not have "a" color, but is translucent, with even a single square centimeter of it showing not only countless colors, but many other effects of light that have only scientific names, such as sub-surface light scattering. Other features do not have mass at all in the way that flesh does: the eyes have numerous non-massive attributes like color, sparkle, transparency, and moisture; hair, unless heavily oiled, does not approximate a solid. Equally importantly, thought we are seldom aware of it, our bodies are in constant motion, although we become acutely aware of it only in its absence: the utter stillness of death can not be mistaken for life.

A naturalistic sculptural representation of a living thing must somehow compensate for all the absent attributes of life, by systematic distortions to the physical shape. For this reason, a naturalistic sculpture can never be "accurate" in the sense that it has the precise physical form of the subject. We see the effect of the absence of such beneficial distortion in the work of contemporary artists such as Duane Hanson and Ron Mueck, who polychrome sculptures that are cast from life, or in Mueck's case, scaled up or down from life castings. Though incredibly carefully painted, these pieces have an eerie, uncanny air--they convince only momentarily, before the viewer is made uneasy, even revolted, by the monsterous exactness.

The practitioners of the new naturalism were mostly academics, because most serious sculptors of the time were from the academies, but the new style was quietly as revolutionary as the work of the modernists. Like modernism, it walked away from the ancient artificiality of sculpture and the formalisms of the canon, much as the Impressionists had stepped away from the artificiality of academic painting, and painted what the eye actually sees. No exact analog of the Impressionist project can exist in three dimesions, because sculpture is an object as well as an image, but the practitioners of the new naturalism were attempting something similar: the representation of the true human figure, rather than an idealized construct conforming to a formal canon of proportion.

Duane Hanson's Man With a Camera (detail), 1991, Edward Onslow Ford's Study of a Head(detail) 1885, Real little boy (detail), 2013

The members of the New Sculpture movement in England, and in parallel movements in Germany, and elsewhere, now used real bodies where the academic tradition had used idealized or mythologized figures; it was as if living people of the present moment had been frozen in time and space. The formalism of sculpting mythological themes persisted, but the New Sculpture had none of the distancing that canonical perfection and classical themes had given Neoclassical and Academic work. While the subjects of the New Sculpture were often beautiful, they were vividly real people. The effect can still be subtly shocking a century later--without the coolness of stylization, it can be as if one has walked in on someone undressed.

The pair of portraits of the famous dancer Anna Pavlova, shown below were made the American sculptor Malvina Hoffman. Pavlova was the a principal dance of both the Imperial Russian Ballet and the Ballets Russes of Sergei Diaghilev. Hoffman, who studied under Rodin, was a prolific sculptor in bronze, marble, and other media in the early Twentieth Century. Both portraits show Pavlova at about 44 years old. The piece on the right is a conventional marble, while the polychromed piece on the left is wax.

Mask of Pavlova 1924, wax, Pavlova, marble, 1925, both by Malvina Hoffman

The wax piece is an unusual example of a successful portrait piece based on a life casting. As such, it may be regarded as the exception that proves the rule, in that part of its power lies in contrast between the vivid polychrome, and her closed eyes and the death-like quality of the wax. This impression is quietly reinforced by its portrayal of the artist at an age at which few dancers are still active (although Pavlova in fact was, until her untimly death from pneumonia six years later, just before her 50th birthday.)

The historical moment for this kind of naturalism in stone may have been unique--it still remains to be seen47 whether there is a place in the contemporary world for it. There is an unfortunate tendency, at this stage in history, to dismiss Victorian culture as excessively sentimental and prim. The Victorian sensibility was indeed emotional; Freud was just getting started, and the pervasive modern pose of knowing irony about what we feel was not yet the mode. But while it is true that there was much silly sentimentality, Dickens, Thackeray, Hardy, Elliot, Yeats, Shaw, and the Brownings were all at work, too.

If we find Victorian culture prim, they would have found us both heartless and timid, immodest about sexuality, yet ignorant about love, and prissy about death. Victorian tastes in women's clothing48 should tell us that the clicheé of the repressed Victorian is missing something major. The sculptural naturalism of these years springs from the same roots as modernism: an intense intellectual struggle by artists and critical thinkers discover what the meaning of sculpture would be in the new industrial culture that was then being born. But it would not have been possible without the Victorian capacity for emotion--you cannot look at people as long, or as closely, as these artists did, unless you love them, and our era lacks the Victorian capacity for love. Beautiful nudity in our time tends to be unrealistic, and realistic nudity ugly. The sculptors of the end of the Century portrayed the body as both achingly beautiful and completely real. We, far more than they, are unwilling to look at bodies as they really are.

The naturalism in nudes of this period makes a startling contrast with both Neoclassical Academic work, and with contemporary hyperrealism, two movements from which it is equally distant in time. Pictured below are are a typical Neoclassical nude (Bertel Thorvaldsen) on the left, and a contemporary hyper-reaslist nude by Ron Mueck on the right. Between them is a naturalistic nude by Francis Derwent Wood, Atalanta, carved in 1907, that illustrates the third path of naturalism. Except for the pregnancy of the third model, the women have similar body types, but while the Neoclassical nude is beautiful, it is an idealization that does not aim to capture, but to override, the model's individuality. The image of the pregnant girl is extremely specific, in no way idealized, but her body, though cast from life, conveys no vital essence-it is just a piece of rubber shaped like a girl. In contrast to both, Atalata seems to capture life itself, while not giving up the immutability of stone. Note particularly the non-Classical proportions of her leg to body length, and the more realistic size of her head, as compared to the Venus, which is almost of action-figure proportions. Divergence from Classical proportions can also be seen in Atalanta's longer waist, larger hands and feet, and relatively heavier hips and thighs.

Thorvaldsen's Venus With An Apple (marble), 1805, Francis Derwent Wood's Atalanta (marble) 1897, Ron Mueck Pregnant Girl (silicone etc.) 2002