CALCULI, OR STONES, IN THE BLADDER. 305 



safe. The Barbadoes aloes, although sometimes very dear, should alone be 

 used. The dose, with a horse properly prepared, will vary from four to seven 

 drachms. The preposterous doses of nine, ten, or even twelve drachms, are 

 now, happily for the horse, generally abandoned. Custom has assigned the 

 form of a ball to physic, but good sense will in due time introduce the solution 

 of aloes, as acting more speedily, effectually, and safely. 



The only other purgative on which dependence can be placed is the cboton. 

 The farina or meal of the nut is generally used ; but from its acrimony it 

 should be given in the form of ball, with linseed meal. The dose varies from 

 a scruple to half a drachm. It acts more speedily than the aloes, and without 

 the nausea which they produce ; but it causes more watery stools, and, conse- 

 quently, more debility. 



Linsked-oil is an uncertain but safe purgative, in doses from a pound to a 

 pound and a half. Olive- oil is more uncertain, but safe ; "but castor-oil, that 

 mild aperient in the human being, is both uncertain and unsafe. Epsom-salts 

 are inefficacious, except in the immense dose of a pound and a half, and then 

 they are not always safe. 



CALCULI, OK STONES, IN THE INTESTINES. 



These are a cause of inflammation in the bowels of the horse, and more fre- 

 quently of colic. They are generally found in the coecum or colon, varying 

 considerably in shape according to the nucleus round which the sabulous or 

 other earthy matter collects, or the form of the cell in which they have been 

 lodged. They differ in size and weight, from a few grains to several pounds. 

 From the horizontal position of the carcase of the horse, the calculus, when it 

 begins to form, does not gravitate so much as in the human being, and there- 

 fore calculous concretions remain and accumulate until their very size prevents 

 their expulsion, and a fatal irritation is too frequently produced by their motion 

 and weight. They are oftenest found in heavy draught, and in millers' horses. 

 In some of these horses they have the appearance of grit-stone or crystallized 

 gneiss. It is probable that they partly consist of these very minerals, combined 

 with the bran which is continually floating about. An analysis of the Calculi 

 favours this supposition. They are a source of continual irritation wherever 

 they are placed, and are a fruitful cause of colic. Spasms of the most fearful 

 kind have been clearly traced to them *. 



Professor Morton, of the Royal Veterinary College, in his Essay on Calculous 

 Concretions, — a work that is far too valuable to be withdrawn from the 

 public view, — gives an interesting account of these substances in the intestinal 

 canal of the horse. Little advance has been or can be made to procure their 

 expulsion, or even to determine their existence ; and even when they have 

 passed into the rectum, although some have been expelled, others have been so 

 firmly impacted as to resist all medicinal means of withdrawal, and a few have 

 broken their way through the parietes of the rectum, and lodged in the abdo- 

 minal cavity. Mr. Percivall, in his " Elementary Lectures on the Veterinary 

 Art," has recorded several fearful cases of this +. 



Other concretions are described under the title of oat-hair calculi. Their 

 surface is tuberculated and their forms irregular. They are usually with- 

 out any distinct nuclei, and are principally composed of the hairy fibrous 

 matter which enters into the composition of the oat. The professor very pro- 

 perly adds, and it is a circumstance which deserves much consideration, that 

 such oats as are husky, with a deficiency of farinaceous matter, are likely to 

 give rise to these accumulations, whenever impaired digestion exists. It is also 



• Veterinarian, IX.. 161. t V«l. II. p. 449. 



