The Only Cure for Measuring

Article by Darren Rousar.

Atelier GleyreAn illustration from Felix Moscheles’s 1896 book, In Bohemia with Du Maurier.

Of the many skills required for successful representational drawing and painting, determining distance is one of the most important. This is true when drawing out of one’s head and all the more when drawing from observation. In fact, when we draw we are constantly measuring. What is the only cure for measuring? Read on, I’ll get to that in a moment.

To ascertain the size, amount, or degree of (something) by using an instrument or device marked in standard units or by comparing it with an object of known size.


According to Google’s definition, above, measuring is done by using an instrument. Unacknowledged in their definition is the fact that your eye is such an instrument.

Of course, your eye is naive, and part of learning to draw is training your eye to accurately measure. Doing that requires comparing a known to an unknown. Perhaps the best “known” exists due to gravity. Take a look at the image below.

An illustration from Charles Blanc's 1867 book, Grammaire des arts du dessin.An illustration from Charles Blanc’s 1867 book, Grammaire des arts du dessin.

What you see depicted is a man atop a sphere which represents the earth. The vertical line running through both represents a plumb line, or the center of gravity. It is through this line that the artist shows us how the human figure, and therefore any solid, can be drawn as if firmly planted on the ground. In fact, the pose of the model in Classical Greek sculpture, and later, in the Paris École, was often chosen to accentuate this geometric or architectural aspect.1

To explain this more concretely, a known vertical (like a plumb line), can instantly show us numerous relationships within the figure. Without reference to it, heads often do not properly rest on the shoulders and feet are often drawn too far off to the side. But, when you drop a plumb, errors such as this cannot happen.

An Etruscan engraved gem stone from the second century BC, showing a man using a plumb line.An Etruscan engraved gem stone from the second century BC, showing a man using a plumb line.

One interesting theory is that advances in sculptural practice predated those in painting. Whether this is true or not, it is often instructive for a painter to look to sculpture, and not only for cast drawings. Relative to the use of the plumb line, “every sculptor takes measurements constantly while working, at first by eye, then using two fingers, and finally with a plumb-line or a piece of string.2

Notice that the author I quoted said that the sculptor takes measurements at first by eye alone. Only after that does he resort to mechanics to check his accuracy. That is a very important point. Use your eye first, then check with your plumb line. If you only measure with the plumb, your eye is learning nothing.

A diagram of Alberti's Finitorium.A diagram of Alberti’s Finitorium, from his book De Statua (On Sculpture), 1466.

The image above shows a device used for measuring a figure in order to transfer those measurements to clay or stone. It appears in Leon Battista Alberti’s De Statua3 and he called it a Finitorium.

As far as I can tell, the Finitorium was to be placed over the model. From there, a plumb was dropped until it hit a part of the body. Then, another was dropped to another part of the body. A measurement was then arrived at. The contraption could then placed over the sculpture and the sculptor could see how far off he was.

Throughout history, sculptors (and painters) have created many devices such as this.

Before we leave the third dimension, take a look at François Rude’s version, below.

This diagram outlines Rude's measuring system.This diagram outlines Rude’s measuring system.

It comes from one of his students, Maximien Legrand, who wrote a biography of him in 1856.

François Rude (1784-1855) was a French sculptor known for his naturalistic looking sculptures. To achieve such naturalism, he developed an elaborate system which was begun by placing actual marks on the model. From those marks, using a plumb line and compass, Rude was able to establish any dimension within the figure.4

How does this apply to two-dimensional drawing and painting? The answer is directly, but in a wholly visual way, as you see in the images below.

To properly use a plumb line, first, the artist must close one eye. Doing this allows him to perceive both the plumb line and the model beyond it. When using both eyes at once it is often difficult to focus on the line; it can appear double.

Plumb line 1

In this first image, above, you can see that I have stood well back from my subject. This allows me to view the whole of it, and the paper on the easel, without moving my head around. This is important because it is the only way to fully compare one aspect to another. When viewed closer in, each aspect is seen as a separate observation. Also note that in the photo I have edited the plumb line to make it stand out against the dark background. The real line is a length of thick, black thread from which is hung a fishing sinker.*

Plumb line 2This image shows what I am seeing when in position.*

The plumb line can represent an actual, drawn line on the paper or canvas. That line is often called a center line, whether or not it is actually in the center of anything.

You will use the plumb line over various areas of your subject. The goal is to ascertain what aspects of the subject are directly in line, above and below, each other. The same relationships must be correctly represented on your drawing and so, after making an attempt at delineating them, you would hold your plumb line up to check. Bear in mind that, as I mentioned earlier, you must first determine what you think are the proper dimensions and placements before you check them with the plumb line. Learn by checking the accuracy of your eye, don’t simply copy over.

Up until this point this post has focused on comparing vertical dimensions using the plumb line. But the plumb line is more versatile than that. It can also be used for horizontal comparisons as well as literal point to point measuring.

Plumb line 3

In this image I am standing back in my viewing position and I have the plumb line stretched tightly between my two hands (note that I have lightened the right half of the line in order for it to be seen in the photo). I have my arms out straight and my elbows locked in place. I have also made certain that it is exactly horizontal by visually laying it atop the upper edge of the drawing board. Once level I lowered my hands, uniformly, until the line visually touched the top of the cast. Then I ran my eye across the line to where it visually touched the paper (near the center, side to side). The hope was that this point was where I predetermined it was, having previously used my naked eye alone. The difficult part is to keep the line exactly horizontal was you both move it into position and as you run your eye across it to the paper.*

For point to point measurements (widths), again, first determine a width by eye. Then, to check your eye, hold the line as you see in the images below.

Plumb line 4

The image on the left shows me measuring the width of the bottom of the cast. On the right you can see that I’ve pulled the measurement over to the paper. Again, I am still back at my viewing position with my arms straight and elbows locked. Any bending of your elbows will change the distance the line is from your eye (and the scene). The result would be an incorrect measurement.*

So what is the cure for measuring?
The only cure for measuring is more measuring.
-R.H. Ives Gammell

The goal is an accurate eye. As I mentioned above, you train your eye by first attempting a dimension without aid. You then check your dimensions via the plumb line. The more you measure, in that order, the more sound the cure will be.

1For more information about the theoretical connection between architecture and French figure drawing (academies), see Richard A. Moore’s, Academic “Dessin” Theory in France after the Reorganization of 1863, from the Journal of the Society of Architectural Historians, Vol. 36, No. 3 (Oct., 1977), pp. 145-174.
2Carl Bluemel, Greek Sculptors At Work, New York: Phaidon, 1969. Page 46.
3Jason Arkles, a prominent sculptor who lives in Florence, has translated De Statua and provided a knowledgable commentary, here.
4A more complete explanation can be found in Anne Wagner’s book, Jean-Baptiste Carpeaux: Sculptor of the Second Empire.

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