90 TIPS AND TOE-WEIGHTS. 



the tubes filled with a thick fluid, the use of which is to nourish and 

 preserve them." Before microscopic observations revealed the exist- 

 ence of these minute tubes, it was thought that the horn lay in layers 

 like the leaves of a book, and the tubes are so arranged as to form 

 these thin strata. The layers are readily separated, and it does not 

 I'equire a long soaking to make the division. The agglutination is 

 moi'e rigid between the tubes at right angles to the layers, and 

 consequently a great force is necessary to rend them asunder. But 

 if the tubes are hardened from dryness, the diameter must be de- 

 creased, and there cannot be a full supply of the fluid, the duty of 

 which is to keep the horn in proper condition. The atrophy of the 

 frog in the shod foot is a striking testimony that the nourishment is 

 lacking. There is no longer the stimulus which exercise gives, and 

 though there is no waste from wear, the supply is cut ofi". The pre- 

 venting the wear at the toe by the application of a tip — or, more 

 properly speaking, a lunette shoe extending as far back as the point 

 of the frog, or a trifle further back — does not seem to retard the 

 growth of the horn at the part covered by the iron. This probably 

 arises from the posterior portion of the foot being so much more 

 pliant, and the stimulus to the secretory vessels of the coronet suffi- 

 cient to keep up the healthy action of the whole of the circle. Since 

 using tips I have noticed that the toe would appear long before they 

 had, apparently, been on a sufficient time to account for the extra 

 growth. It was ascribed to the wearing away of the heel, while the toe 

 was guarded; but a late experiment shows that this was only partially 

 the cause. On the 19th of January, X X was shod with tips 

 weighing seven ounces each. Pi-evious to that he had been 

 without anything on his feet, and was turned, during the day, 

 into a small lot. There was very little wearing of the horn, 

 and when the tips were put on the heels had to be low- 

 ered to give the proper bearmg. When this reduction was 

 made, a gauge was set so as to give an accurate measure- 

 ment from the ground surface to the junction of the hair and horn. 

 At this date, the 16 th of February, four weeks since the tips were 

 put on, the toe is quite long, altogether too much so to give a jiroper 

 bearing to the foot, but the gauge shows that the wear at the heel 



