Eclipse is an image of the Sun, Moon and Earth to scale in the position of a solar eclipse. The Sun, Moon and Earth are exposed on to photographic paper using a photogram process. This is an image that is never seen to scale in a textbook as the distance from the Earth to Sun is so large that the Earth would be too small to see if printed on a standard sized piece of paper.
To make the Moon and Earth large enough to be visible 100 sheets of standard sized paper (either 8" x 10" photographic paper, A4, or Letter) are used. The Sun almost fills the first sheet, then there are 98 sheets of blank paper before the Moon and Earth can be seen on the 100th sheet. If each piece of paper is layer size by size the correct horizontal scale is demonstrated. So the horizontal dimensions of the work in its various sizes are: 8" x 10" paper is 800"/2032cm long, A4 is 827"/2100cm long and Letter is 850"/2159cm long.
The configuration however is up you and could be displayed in a number of rows, for instance 5 rows, each 20 sheets long; or the first sheet, then a stack of 98 sheets, then the last sheet on a table. These paper sizes are so familiar to people that they can be used as rulers, in fact people are probably much more familiar with their country's standard paper size than they are with a ruler. So the image of the Sun, Earth and Moon, their relative scales and the paper size is enough to convey the enormity of scale involved with these objects that we are so familiar with.
Eclipse is available as a free download in A4 and Letter sizes