THE NERVOUS SYSTEM 373 



restlessness of the patient and forceful labour pains are the chief obstacles 

 to a return of the viscus, and some restraint must be exercised to suppress 

 them. The use of cocaine in a four per cent solution has been found 

 helpful in producing more or less local anaesthesia, and removing the dis- 

 position to renewed expulsive efforts which the presence of the operator's 

 hand induces. 



Subsequent treatment consists in keeping the animal on soft diet 

 and under good hygienic conditions, and the administration of anodyne 

 medicines if pain is experienced. If a subject of this accident is again 

 bred from, increased risk attends parturition. 



4. THE NERVOUS SYSTEM 



The possession of a nervous system is not essential to life, since in 

 the whole vegetable kingdom, as well as in the lower animal organizations, 

 multitudes of living forms are to be seen, which, although unprovided 

 with nerves, are yet perfectly capable of preserving their independence 

 and of holding their own in the struggle for existence; but wherever it 

 is found, owing to its wonderful sensitiveness to impressions, it fulfils 

 the important purposes of bringing the animal into relation with the 

 outer world, of enabling it to respond to those impressions by inducing 

 muscular movements which eftect either local or general change of place 

 or form, and finally of linking together, as with a subtle net-work, the 

 most remote organs of the body, enabling each part to co-operate with 

 the rest for the general good, and uniting or integrating them into a 

 common whole. 



Originally the nervous system is composed of a soft living mobile 

 substance, termed " protoplasm", from which all parts of the body are 

 formed; and it is only by degrees that it acquires its special endowment, 

 that of generating nerve energy, which, like other forms of force, is subject 

 to laws of its own, and can either be stored up, liberated, intensified, or 

 exhausted under appropriate conditions. 



In the horse, as in all the higher animals, the nervous system presents 

 two parts for examination, one of which, and by far the larger, is named 

 the cerebro-spinal, the other the sympathetic system. 



The cerebro-spinal system is adapted to respond to various kinds 

 of impressions made upon the organs of sense, as the eye, ear, skin, tongue, 

 and nose, to conduct those impressions through cords, which are termed 

 nerves, to central organs represented by the spinal cord, medulla oblon- 



