FIELD NATURALISTS' CLUB. 255 



The following is the method suggested by Mr. Hutcheon, 

 the Cape Colony veterinary surgeon : — " In the case of horses 

 which are grazed and only partly kept in stable, a good plan is 

 to wipe the following parts well with a cloth saturated with a 

 mixture of equal parts of paraffin and oil, viz., from the anus to 

 the sheath between the thighs and around the hind legs, then 

 along the bell}'' and chest and around the fore legs before letting 

 them out to graze. It is difficult to get a cheap preventive which 

 is both harmless to the animal and cleanly to use. To moisten 

 the coat with a weak solution of any of the tar or carbolic acid 

 dips would also answer if frequently applied." 



The editor of the Cape Agricultural Journal writes " I have 

 tried sulphur with horses, putting a mixed streak of flowers of 

 sulphur and fat all along the back from mane to tail with most 

 capital effect. Sulphur has a peculiar power of diffusing itself 

 all over the animal and the sulphurous acid gas slowly given 

 out is most obnoxious to all insects." 



Another authority remarks that when the ticks have 

 effected a lodgement in the horse's ears, nostrils Are., " a little 

 train oil, chloroform, carbolic acid, sweet oil, or dusting with 

 calomel will be effective." 



Thus far it has been assumed that the cattle have already 

 been attacked by ticks, and various suggestions have been made 

 to cleanse them from these parasites, and keep others off as long- 

 as possible. 



If, by other means, it is possible to make the skin of the 

 cattle so revolting to these parasites that the}' will not in the 

 first instance attach themselves to it, there will then be no need 

 of these spraying operations. This can be effected, as already 

 hinted by introduction of substances into the animal's food. 



The addition namely of small quantities of sulphur to the 

 solid food appears to have the desired result. Externally applied, 

 sulphur has probably on local action of itself, but part of it is 

 changed by contact with the acid sweat into sulphuretted 

 hydrogen. 



The following seems to be the physiological changes which 

 take place during the passage of the sulphur, through the 

 animal's body to its skin. Sulphur taken in with the food passes 

 the stomach unaltered. In the intestines a small portion is 

 changed into sulphides of hydrogen and the alkalies. Part of 

 these sulphides pass into the blood and into the tissues from the 

 blood, and act chiefly upon the central nervous system. The 

 sulphides in the tissues are variously excreted. ]3y the kidneys 

 they are excreted as sulphates : if in excess, part is also excreted 

 in the form of sulphides. By the skin they escape as sulphides, 

 giving the characteristic foul odour to the perspiration and 

 somewhat increasing its amount. 



