324 CHAPTER 42. 



flow of the blood through the vein which passes over it, and renders it 

 varicose. The dilatation of its coats takes place just under the seat of 

 the bog-spavin. There is no direct remedy, but any treatment which 

 lessens the bog-spavin will decrease the tendency to retardation in the 

 upward flow of the blood. No great harm results from the dilatation of 

 the vein. The greater part of the swelling is always due to the Bursal 

 Enlargement not to the vein. 



CHAPTER 12. 

 DETECTION OF THE SEAT AND CAUSE OP LAMENESS. 



649. Introduction. 650. Detection of the seat and Cause of Lameness. 

 651. Mode of examining a horse. 652. Whether lame before or behind, to 

 be first ascertained. 653. Side, on which the horse is lame, to be next 

 ascertained. 654. If lame before, whether in the foot or elsewhere. 655. 

 If not lame in the foot, and yet more lame on hard than on soft ground an 

 Exostosis may be suspected. 656. Of lameness in the fore-hand, when the 

 horse is more affected on soft than on hard ground. 657. Lameness in the 

 Hind Quarters. 658. Sprains of the Loins and Stringhalt. 659. Rheu- 

 matism as a cause of Lameness. 660. Accidents and such like causes of 

 Lameness. 



649. Introduction. 



Lameness is only a symptom of disease. It may be produced either by 

 pain, by inability, by malformation, or by accident ; or it may arise from 

 disease of the cerebral or nervous system, as in injuries of the spinal 

 cord or in stringhalt. 



Lameness is usually, but not invariably a sign of pain. In anchylosis 

 of a joint, for instance, there is decided lameness from mechanical im- 

 pediment, but no pain. 



Again, loss of elasticity of movement, such as is common in old horses 

 or in animals which have done much work, may exist to a degree scarcely 

 distinguishable from lameness. 



It might, at first sight, seem a very simple thing to say, whether a 

 horse is lame or not. It is" not so, however, in many cases. Old, or 

 hard-worked horses, as just mentioned, sometimes go stiff to a degree, 

 which may easily be mistaken for lameness, unless due allowance is made 

 for age, &c. Again, some horses, which are very wide in their chests, 

 roll in their action to an excessive degree. Other horses, if constantly 

 driven in harness, acquire a peculiar hitch in their trot, which is not 

 really lameness. If. the animal is sound, this will probably disappear 

 when he is trotted slowly in hand with a very loose rein. Others, espe- 



