574 NEEVOUS DISEASES. 



in the sun, like those on tramways, should have short stages, and 

 should be watered immediately after doing their turn. Probably 

 the best mechanical protection for animals at work in the sun is 

 a thick shade (of wood or stout leather, for instance) for the 

 eyes and forehead. There is no doubt that the effect of intense 

 glare on the retinae of the eyes is a potent aid in bringing on 

 an attack of sunstroke. In our own cases, we may experience 

 the great relief and actually cooling effect of blue, green, or 

 neutral-tinted glasses when worn in the open on a very hot and 

 sunshiny day. The retina, which is an expansion of the optic 

 nerve and which is close to the brain, is peculiarly sensitive to 

 heat rays as well as light rays. Also, the brain is nearer the 

 surface at the forehead, than at any other part of the head. 

 Pith sun-protectors placed over the top of the head and poll, 

 and over the loins, as is often done in India, are of little value 

 in guarding against sunstroke, as compared to that of thick 

 shades for the eyes and forehead. The sun-bonnets used during 

 summer on horses in England, give no protection against sun- 

 stroke ; for they do not shade the eyes and forehead, and are 

 far too thin. Everyone who has travelled, knows that a straw 

 hat is not of the slightest use for shielding the head against 

 the rays of the sun in the tropics, for which object a thick 

 head covering of a material that is a bad conductor of heat (such 

 as a turban or pith helmet) is indispensable. When horses, by 

 the fact of their "blowing" without having been worked, and 

 being out of spirits without cause, are seen to bear hot weather 

 badly, special precautions should be taken with them. It will 

 be found that such animals will generally have an unusually hot 

 skin, and will perspire with difficulty; in fact, they will be 

 feverish. They should have a plentiful supply of salt (p. 593) and 

 may, from time to time, get an ounce of bicarbonate of soda 

 (baking soda) in their water every day for a week or ten days. 

 Their supply of drinking water should of course be unlimited. 



TREATMENT. — ^In cases of threatened sunstroke, as would be 

 made manifest by quickened respiration and marked rise of tempera- 

 ture, say, over 103° F., I would advise that the animal should get 1 

 lb. of Epsom salts in a couple of quarts of water ; and after that, 1 J 

 drachm of phenacetine every four hours (according as control over 

 the temperature is obtained), or 1^ drachm of tartar emetic in his 

 drinking water for a few days. He should have a constant supply 

 of water to drink, and his food should be restricted to " green 

 meat " (grass, lucerne, etc.), carrots and other suitable roots. If 

 this scale of diet cannot be carried out in its entirety, he should 

 have bran mashes or boiled barley, in strictly moderate quantities, 



