422 
Journal of Agricultural Research 
Vol. XXV, No. 10 
EXPERIMENTAL 
We wished to know the surface area of some of our experimental 
steers, under observation at the time, so our first measurements of cattle 
were made on living animals. The first step was to prepare an inelastic 
mold of one-half the body, that is, of one side. This was accomplished 
by pasting strips of strong manila paper, gummed on one side, to the 
hair of the animal, and building up on this foundation until the mold was 
rigid enough to be handled. Before it was removed the median line was 
marked so that when trimmed the mold represented exactly one-half the 
surface area. The mold was usually made in four parts. Each leg made 
up a part, the shoulder, neck, and head made up another, and the body 
and hind quarter made up the fourth. The outside of the ear was also 
measured and the area multiplied by two. The steers were gentle and 
accustomed to being handled, so with care it was possible to obtain a very 
accurate mold. When dry it was cut into pieces that would lie flat. 
These pieces were traced on blue-print paper, and the tracings cut out 
and weighed. The weight of the paper per square centimeter was 
determined, and then it was a simple matter to calculate the surface 
area of the animals. Before adopting this method we assured ourselves 
that the paper used was sufficiently uniform for our purpose. 
The method employed for measuring the surface area of the slaughtered 
cattle consisted in tracing the outline of the entire hide on a large sheet 
of paper made by pasting strips of heavy wrapping paper together. 
With a little care the hide could be made to lie fiat and an accurate 
tracing obtained. The area was determined by drawing rectangles and 
triangles on the tracing of the hide and measuring these. This method 
also was used for determining the surface area of the swine. In most 
cases only the hide from half of these animals was measured, that from 
the right side of the body. 
In one case we had an opportunity to compare the two methods of 
determining the surface area of cattle. Steer No. 528 was killed not long 
after his surface area had been determined by use of the mold. The hide 
was removed and measured, and the two methods compared. 
Area determined from hide. 64,344 sq. cm. 
Area determined from mold. 64,028 sq. cm. 
Difference.. 316 
The difference in this case is less than 0.5 per cent of either determination. 
MEASUREMENTS TAKEN 
A number of measurements were taken on these animals, but the 
only one used was the 41 length of body.” The length of body of cattle 
was taken as the distance measured with a tape from the point of the 
withers to the end of the ischium. The length of body of swine is the 
distance as measured with a tape from the point of the withers to the 
root of the tail. 
The chief difficulty encountered in using the formula lies in the uncer¬ 
tainty as to the exact position of the “point of withers.” We attempted 
to use some other measurement, but failed to find one more satisfactory. 
It is impossible, of course, to secure any cooperation from animals in 
taking these measurements, and, if any portion of the neck is included, 
the position in which they stand affects very materially the result. 
