The Locomotor Apparatus. 347 



which is not placed under the centre of gravity, as in the 

 gallop, but behind it, the animal being balanced on one 

 limb only (3) ; in the fourth stage the off' hind and near 

 fore come to the ground together, so that the body is now 

 balanced on three legs, viz., near fore and both hind (4) ; 

 in the fifth stage the off fore comes to the ground, but as it 

 does so the near hind rises — the animal is still left on three 

 legs, viz., both fore and off hind (5) ; in the sixth stage the 

 near fore and near hind, and, slightly later, off hind, leave 

 the ground, the horse being balanced on the off fore only 

 (0) ; the next movement is a repetition of the first, the off 

 fore pressing the body upwards. 



The Gallop is a very difficult pace to describe, and the 

 analysis I give of it here is from one of Mr. Muybridge's 

 numerous and beautiful instantaneous photographs (Fig. 44). 

 To this gentleman the scientific world is indebted for an 

 accurate knowledge of how animals use their legs in pro- 

 gression. 



The Gallop consists of seven stages. We will elect to 

 describe it from the time the animal is in the air, no legs 

 being on the ground, but all four of them brought well 

 under the body; this is the first stage (1). In the second, 

 one hind-leg, say the off, comes to the ground (2) ; in the 

 third stage the near hind comes to the ground, the horse 

 now being balanced on two hind-legs, both fore being in 

 the air (3) ; in the fourth stage the off fore comes to the 

 ground, but the horse is not balanced on three legs as in 

 the canter, for at the moment the off fore came to the 

 ground the off hind was extended, leaving the animal on 

 diagonal legs, viz., off fore and near hind (4) ; in the fifth 

 stage the near hind leaves the ground, the animal being 

 balanced on one fore leg, in this case the off fore (5) ; in 

 the sixth stage the near fore comes to the ground (6a), and 

 the off fore leaves it (Job) — the body is, therefore, again 

 supported on one fore leg ; in the seventh stage the body 

 passes over the near fore leg (7), and by a contraction of 

 its muscles the entire weight is lifted off the ground, and 

 the body propelled forwards and upwards (1). 



