18 



STRUCTURE AND FUNCTION 



himself, going collectedly and executing each step with an ex- 

 treme degTce of flexion and the utmost precision (Fig. 15). 



Pace is a rapid, two-beat gait, in which the lateral fore and 

 hind legs act together (Fig. 16). It is characterized by the 

 readiness mth which pacers can get away at speed, a minimum 

 of concussion, more or less side motion, the absence of much knee 

 fold (although some pacers are trappy), and the necessity for 

 smootli, hard footing and easy draft, for its execution. It is 

 difficult for most pacers to go in deep or heavy footing, such as 



Fig, 14. — The fast trot, characterized as a diagonal gait of extreme extension and rapidity 



of stride. 



fresh snow, sand or mud, and they have a jerky, unsteady way 

 of pulling a wagon, if any pull is necessary. The increased 

 draft of an additional person up behind or of a rough bit of road 

 will swing most pacers into a trot if they can trot at all. Jogging 

 down hill will force some trotters to pace, while an up grade will 

 set pacers to trotting. The joace is more essentially a speed than 

 a road gait. 



Amble is a lateral gait usually distinguished from the pace 

 by being slower and more broken in cadence. 



Rack is a fast, flashy, four-beat gait, more clearly defined 

 by the discarded name " single foot." It is rarely executed vol- 

 untarily but under compulsion of hand and heel, and is charac- 



