(Note: The text and images are taken from “A Study of Farm
Animals,” by Charles S. Plumb, 1924. Click on photos to
enlarge.) “The use of the horse, in spite of the automobile, is
very general in both town and country. He is suited to do many
things for which the motor is not fitted. He is a more
economical producer of power in short hauls than is the motor,
and he is as necessary as ever on the hill farms and where small
areas are cultivated. According to the 1920 census we had in the
United States some 20 million horses and over 5 million mules.
These horses had a farm value of $2,000,000,000, and the mules
were valued at half a billion dollars, so we may see that the
production of the horse in America is a great industry…. The
work of the horse and what he can accomplish depends upon his
weight, his muscular development, and his endurance. What is
knows as horse-power, is the power necessary to raise 33,000
pounds at the rate of one foot a minute against gravity. The
real measure of horse-power is based on