56 Scats and Saddles. 



attain his object, whatever that may be — as also to save 

 his horse's back, and his own person, and perliaps 

 neck. 



To begin with the under surfoce 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 mechanical 

 principle applies to both — namely, that the larger the 

 surface over which a given amount of pressure is equa- 

 bly 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 backbone, 

 which must remain altogether out of contact. The 

 notion of making one portion come into closer con- 

 tact than another, "giving a gripe," with the intention 

 of preventing the saddle slipping, is altogether erro- 

 neous, 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 increase 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 accurately 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 consequently 

 the less risk of sore back, provided always that the 

 pressure be equably distribiUed over the whole surface. 

 To make a saddle a yard long, and put the weight alto- 

 gether at one of its extremities, is not the way to attain 



