MEGRIMS. 101 



to break these bones must likewise irreparably injure the delicate and im- 

 portant organ which they protect. 



The ridg-e, or outer and upper part of the orbit of the eye, is occa- 

 sionally fractured. It happens from falling", or much oftener from violent 

 blows. The "slightest examination will detect the loosened pieces, but a 

 professional man alone can here render effectual assistance. All, however, 

 that he can do will be gently to replace the parts in their natural situation, 

 and contrive to confine them there by adhesive plasters ; to obviate in- 

 flammation by bleeding, physic, and low diet, and leave the rest to nature. 



We proceed then to the diseases of the head, and the first of these is 

 PRESSURE ON THE BRAIN. This may be produced by some fluid thrown 

 out between the membranes, or occupying and distending the ventricles of 

 the brain. In the grown horse this rarely occurs, but it is well known to 

 breeders as an occasional disease of the foal, under the name of " water in 

 the head." The head is either very much enlarged, or strangely deformed, 

 or both ; and the animal dies either in the act of foaling, or a few days 

 after the birth. 



MEGRIMS. 



There is another kind of pressure on the brain, resulting from an un- 

 usual determination or flow of blood to it. This .organ requires a large 

 supply of blood to enable it to discharge its important functions. It is 

 supposed that ten times more blood flows through the brain than through 

 any other part of the frame of equal bulk. Nature, in the horse more than 

 in many other animals, has made some admirable provisions to cause this 

 great quantity of blood to flow into the brain without much velocity, and 

 thereby to lessen the risk of suddenly overloading it or rupturing its 

 vessels. The arteries pursue their course to the brain in a strangely wind- 

 ing and circuitous manner ; and they enter the skull through bony holes 

 which will admit of the enlargement of the vessels only to a very limited 

 extent : yet, from various causes, of which the most common is violent 

 exercise in a hot day, and the horse being fat and full of blood, more than 

 the usual quantity will be sent to the head :— or from some negligence about 

 the harness, as the collar being too small, or the curb-rein too tight, the 

 blood will be prevented from returning from the head : and thus the larger 

 vessels of the brain will be too long and injuriously distended, and, what 

 is of more consequence, the small vessels which run through the sub- 

 stance of the brain will be enlarged, and the bulk of the brain will be 

 increased, and it will press upon the origins of the nerves, and produce, 

 almost without warning, loss of power and consciousness. 



The mildest affection of this kind is known by the name of Megrims. It 

 comparatively rarely happens when the horse is ridden ; but should he be 

 driven, and, 'perhaps, rather quickly, he may perform a part of his journey 

 with his usual cheerfulness and ease, when all at once he will stop, shake 

 his head, be evidently giddy, and half unconscious. In a minute or two 

 this will pass over, and he will go on again as if nothing had happened. 



Frequently, however, the attack will be of a more serious nature. He 

 will fall without the slightest warning, or suddenly run round once or 

 twice, and then fall. He will either lie in a state of complete insensibi- 

 lity, or struggle with the utmost violence. In five or ten minutes he will 

 begin gradually to come to himself; he will get up and proceed on his 

 journey, yet somewhat dull, and evidently affected and exhausted by what 

 had happened, although not seriously or permanently ill. 



This is a very dangerous disease — dangerous to the horse, which wul 



