Materia- Medica . 



159 



tion. If this is not attended to the fluid will gravitate 

 among the hair, and flow downwards, causing useless and 

 often extreme irritation. In the hands of amateurs the 

 following ointment is safest . 



2. Ointment. Powdered cantharides, 2 oz. ; oil of tur- 

 pentine, 2 fluid oz. ; oil of origanum, i fluid oz. ; yellow 

 resin, i oz. : hog's lard (free from salt), 16 oz. Mix the 

 cantharides, resin, and lard together, and heat in a 

 water-bath for eight hours ; then remove, strain, and set 

 aside to cool a little ; next add the turpentine and origa- 

 num ; agitate thoroughly, after which allow the whole to 

 set. 



To ensure the speedy action of a blistering ointment, 

 first clip the hair closely by means of sharp scissors or an 

 efficient clipping machine. Over the part thus denuded 

 the ointment is to be spread in successive quantities, each 

 being thoroughly rubbed in, and at the close a thin layer 

 should be evenly spread over. Great judgment is re- 

 quired as to the quantity used. Finely bred animals do 

 not tolerate mre than half the quantity required by a 

 large, coarse draught horse. An excess, therefore, will 

 do harm by exciting undue irritation, and probably lead 

 to ugly blemishing, besides augmenting the original 

 malady. 



CAUSTICS. 



Substances capable of producing chemical action upon 

 the living tissues are termed caustics. The effect is equi- 



The Budding Iron. 



valent to burning or decomposition. They are of two 

 kinds the actual cautery, or iron heated to redness ; and 



