102 HANDBOOK OF THE TURF. 



of scientific analysis. Repeated — if the movements succeed 

 each other with excessive rapidity, with or without an increase 

 in speed. Short — when their strides are cramped and narrow. 

 Strong — when the action is rapid, energetic, easy, high, extended 

 and rhythmical. Uniform — resulting from equal length of 

 steps. 



Gait, Registering the. The methods of registering 

 the motions of the horse known to science are called the 

 graphic, hydrostatic, electrical, and photographic. M. Marey, 

 principal of the College de France, was one of the first to study 

 the locomotion of the horse by means of what he termed the 

 graphic method. This was done by means of compressed air 

 in two drums or metallic cases, each closed above by a rubber 

 membrane to which was fixed a lever capable of executing to 

 and fro vertical movements. These drums were connected by 

 rubber tubes. When filled with air the pressure exercised upon 

 one forced the air through the tube into the other drum, whose 

 lever and membrane it elevated, and when the pressure ceased 

 it relapsed. Hence this unity of action transmitted movements. 

 These drums w^ere again connected with a cylinder covered by 

 a layer of smoked paper, which was made to turn regularly by 

 clockwork. This moved a registering needle by which the 

 least displacement left its trace u^Don the paper. The paper 

 retained the tracing of vertical undulations corresponding to 

 the pressure transmitted to the registering apparatus by the 

 concussion and contact of the hoofs upon the ground — four 

 recording needles corresponding to the four feet of the horse, 

 each foot being provided with an India rubber pneumatic bulb, 

 so that with each step tiie bulb was compressed, forcing a portion 

 of the air into the registering drum or cylinder. When the foot 

 w^as raised the bulb again became filled with the air which was 

 expelled from the other when it resumed its original form. 

 This device was not always practical in its operations, and 

 M. Marey next invented a leather bracelet which was attached 

 to the ankle of the horse, and upon which was a rubber bulb, 

 and by an ingenious arrangement of copper plates and lead 

 balls connected it by transmission tubes to a registry drum 

 carried in front of the rider on the saddle, by which means the 

 concussions were registered. He followed this with another 

 invention which consisted of electric needles and conducting 

 wires by means of which an apparatus closed and opened an 

 electric current during the contacts and elevations of the horse's 

 feet, and hence the notations of gait were obtained and regis- 

 tered. The hydrostatic method of registering the gaits in man 

 was invented by H. Vierordt, and applied to the study of the 



