46 SEATS AND SADDLES. 



every rider to ascertain exactly what lie wants, and 

 how to attain his object, whatever that may be as also 

 to save his horse's back, and his own purse, and per- 

 haps neck. 



To begin with the under surface of the saddle the 

 portion coming in contact with the horse's back we 

 find two principal points for consideration, its shape 

 or form, and its size or extent. One general mechan- 

 ical principle applies to both namely, that the larger 

 the surface over which a given amount of pressure is 

 equably spread or divided, the less will be the action 

 on any given point of the other surface in contact ; and 

 this translated into plain English means, as regards 

 shape, that the under surface of the saddle should bear 

 as nearly as possible the same relation to that part of 

 the horse's back it is intended to occupy, as a mould 

 does to the cast that is taken from it, always saving 

 and excepting that strip lying over the horse's back- 

 bone, which must remain altogether out of contact. 

 The notion of making one portion come into closer 

 contact than another, " giving a gripe," with the inten- 

 tion of preventing the saddle slipping, is altogether 

 erroneous, because it is the sum total of the pressure 

 which produces the cohesion between two surfaces ; its 

 being concentrated on one point or line does not in- 

 crease this amount, but is very likely to make a hole 

 in the horse's back. Which part of the horse's back 

 it should be fitted to has been " dimly shadowed forth" 

 in Chapter I., but shall be more clearly and accu- 

 rately determined in the course of this present one. 



As regards size or extent of surface the meaning is, 

 that the greater this is with a given weight, the less 

 will be the pressure on any given point, and conse- 



