PREVENTION AND TREATMENT OP 1 SCABIES. 187 



plastered and entangled especially, towards the surface. This 

 renders the material difficult to work ; it interferes with the 

 working of the machinery through which it has to pass, and 

 it causes the wool to tear and break up. These results vary 

 according to the quantity of white tar or Venice turpentine 

 applied. 



Common tar is a substance which the wool-merchant con- 

 demns. It renders the fleece unfit for use, except for dark- 

 coloured goods, and when applied in large quantities, it is apt 

 to pack the fleece to such an extent as really to injure the 



leep. Deaths have occurred in far greater numbers than 

 be imagined from this cause. American tar is now 



)t to be had, and we hope that Scotch farmers will be 



iduced to give over using tar in the way they have ap- 



lied it of late years. 



Oil of tar kills the parasites, but it has also been known 

 kill the sheep. It does not mix well with other smearing 

 stuffs, and has not the tenacity which, according to some, is 

 the most valuable quality of common tar. 



Resins employed, to stiffen salves have been found even 

 more objectionable than Venice turpentine, and have not, as 

 a rule, the same power to kill vermin. 



Fats, Oils, and Soaps. These materials are often used 

 when very ill adapted for smearing. Some of the fats are 

 rancid and mixed with fifteen, twenty, or even thirty per cent, 

 of water ; so that the farmer who thinks he is smearing a 

 sheep with 12 ounces of grease, is really only applying 8, 

 and paying dear for water, which he knows is not a good 

 material for his fleeces. Other fats colour the wool and give 

 it a golden tint. Few oils are of use. Fish oils are 

 objected to much by experienced wool merchants, and all oils 

 are deficient in the tenacity required in any smearing stuff. 

 They may be used in low countries occasionally, but even 



