592 



ROWELLING. 



tioner was mistaken in his estimate of the immediate clanger, 

 extensive and lasting blemish was the consequence. We 

 have in the liquor ammonia an agent quite as formidable 

 as boihng water or heated iron, but it is rather longer in 

 displaying its force ; wherefore it allows time for watching 

 its action, and of checking it the instant it has sufficiently 

 blistered the skin. It is true the Uquor ammonia upon the 

 skin cannot be removed, neither need it be counteracted. 

 Ammonia is like steam, only powerful when confined. The 

 ordinary soap liniment if covered over, would, because of 

 the ammonia it contains, produce a lasting blemish ; but 

 every veterinary surgeon knows how very harmless a pre- 

 paration that is when simply rubbed upon the surface. So 

 when we desire the active effects of Uquor ammonia, we 

 double a blanket or rug four or five times and hold it over 

 the liquid. It takes from ten to twenty minutes to raise a 

 bhster, and it consequently can from time to time be observed ; 

 and when its action has reached the wished-for point, all 

 we have to do effectually to stop it is, to take away the 

 rug or blanket. That removed, the free surface and the 

 heat of the body occasions the ammoniacal vapour to be 

 dispersed, and the animal is safe. 



ROWELLING. 



Rowels act as foreign substances within the body ; they 

 cause irritation and suppuration, whereby more deep- 

 seated inflammations are supposed to be removed : they 

 are, however, often very convenient, because they stand as 

 signboards to show the proprietor that something has been 

 done. The common mode of making a rowel is after the 

 following manner. A slit is first made by means of the 

 rowel scissors, on any part of the integuments held between 

 the finger and thumb ; with the handle of the scissors sepa- 

 rate from its cellular connexions a circle of two or three 

 inches in diameter, into which introduce something to pre- 

 vent the reunion of the skin. A piece of circular leather, 

 tolerably stiff, with a central hole, is a very common sub- 

 stance used ; but is objected to by some, on account of the 

 difficulty of changing it without injuring tlie skin : tow, as 

 more pliant, is frequently introduced into this cavity. If 

 the rowel runs freely, it should be dressed every day, by 



