1904.] Experiments in Dipping Sheep. 



At the request of the Departmental Committee appointed by 

 the Board of Agriculture to enquire into the dipping and treat- 

 ment of sheep, Professor Winter carried out 



Experiments in at the farm of the University College of 



Dipping- Sheep. AT ■ TTT ' „ r . 



North Wales, Bangor, a series of experi- 

 ments to test the effects of various dips on the parasites which 

 attack sheep, and also to determine the effect of the dips on 

 wool. The experiments may be divided into three series. 



In the first series of experiments the Committee proposed to 

 use sixteen different preparations, representing well-known 

 types of home-made and manufactured dips. One of these, a 

 sulphur-magnesia compound, it was eventually found impossible 

 to obtain, as it had ceased to be manufactured. The total 

 number of different dips employed was, therefore, fifteen. These 

 were tried during July and August, 1903, in order to determine 

 :heir effect on keds {Melophagus ovinus). 



This is probably the most widely distributed of the parasites 

 which affect sheep. It is often erroneously called " the tick." 

 Die dips employed were, in many cases, proprietary prepara- 

 :ions, and in order to avoid referring to the makers by name 

 :hey are distinguished by numbers, as follows : — 



I. — Arsenic and washing soda : 2^ lb. of arsenious acid and if lb. of ordinary 

 washing soda per 100 gallons of dip-bath. 

 II- — Arsenic and caustic soda : 2| lb. of arsenious acid and \ lb. of good, dry 

 caustic soda per 100 gallons of dip-bath. 

 III. — Arsenic, washing soda, and sulphur : The same as No. I., with the 

 addition of 4 lb. of flowers o sulphur. In the second experiment 

 8 lb. ot sulphur were used. 



IV. — Arsenic and sulphur : A combination of arsenic and sulphur, containing 



5 lb. of free sulphur per 100 gallons. 



V. — Soluble sodium compounds of sulphur, together with sulphur in a free 



state. 



VI. — A solution of calcium sulphide : Prepared by boiling together 25 lb. of 

 sulphur, I2| lb. of lime, and sufficient water until the solution was of a 

 dark red-brown colour, straining and making up to 100 gallons of the 

 dip-bath. 



VII. — Sulphur magnesia : Not used. 



VHP — Carbolic acid : i-| gallons of liquid carbolic acid (97 per cent, of real tar 

 acid), 5 lb. of soft soap, to 100 gallons of water. In the second 

 experiment only § gallon of carbolic acid was used. 

 IX.— Mixed carbolic acid and arsenic : Equal parts of No. I. and No. VIII. 

 X.— Tar acid and other tar products. 

 XI - — Pitch oil : One part of soft soap, two parts of pitch oil, and to each gallon 

 of this mixture 1 quart of seal or whale oil. One part of this complete 

 mixture being used to thirty parts of water for the dip-bath. 



