104 
ANIMALS IN MOTION. 
almost precisely the same relative positions in which we 
found them in i. The two remaining phases commence 
another stride. 
As no chronograph was used in the investigation of 
1879, the time made in a mile, or fraction of a mile, was 
kept by a stop-watch. The stride illustrated was one of 
three hundred and ten, or thereabouts, made by the horse 
around a mile track in two minutes and sixteen seconds. 
A mile has been trotted over in several seconds less time, 
but the series fairly represents the stride of a first-class 
trotting horse at the height of his speed. 
The length of the stride is readily measured. The 
lines on the track were twelve inches apart ; they show 
the distance to have been approximately two hundred 
and four inches, sixty-six of which were made without 
contact with the ground. Some horses making a stride 
of not much greater length have been photographed, with 
the result of showing the transit, without support, to be 
fully one-half the length of the stride; this, of itself, is, 
however, no evidence of a more rapid motion than when 
the feet are on the ground for a longer period. 
In the analyzed stride the sequence of phases are— 
A ) 
k ) 
k t 
k k 
k ; 
k t 
k i 
k t 
k 
-A 
- A- 
- tJ 
- 0- 
- 0- 
123456781 
For the purpose of instituting a comparison between 
the strides of a trot made under different conditions, this 
same horse was saddled, and went around the track with 
a jockey on his back. The time was three seconds more, 
the stride nine inches less, and the distance over which 
the horse was carried by its momentum, free from contact, 
was reduced by twenty-four inches. 
As the consecutive phases recorded above are not 
invariably followed, even by the same horse, in con¬ 
sequence, perhaps, of inequalities on the surface of the 
track, or from some other cause, it will be a safer plan to 
give a broader significance to a stride of the trot, and 
to represent it with a more elastic diagram. 
For general purposes this definition is perhaps sufficiently 
exact. 
Series 29 is of a good, well-trained horse, going at a 
moderate speed, with an easy stride. 
Series 30 is an example of a stride free from the 
restrictions of harness or a rider. 
Series 33 determines that, no matter how heavily built 
a horse may be, or how slowly he is trotting, the legs 
relinquish the support of the body twice during each 
stride ; the feet may be merely dragged over the surface, 
but for a time they are practically inert. This occurs in the 
