654 MANAGEMENT OF SHEEP EXTERNAL PARASITES 



different districts. While tobacco, which adds materially to 

 the cost of a dip, may be useful among Blackface sheep, 

 where there is the danger of a few undipped sheep 

 mixing with those which have been dipped, it may be left 

 out in those parts of the country where the sheep are so fully 

 under control that they can be confined after dipping within 

 enclosures where chances of contamination would be im- 

 possible. Tobacco is liable to discolour white wool and 

 reduce its value. The amount of dip material necessary in 

 autumn for 100 sheep may be stated in round figures at 80 

 gallons for mountain breeds and 100 gallons for the larger 

 lowland sheep, smaller amounts being sufficient in both 

 instances for recently shorn sheep and for lambs. 



Caution. The various simple ingredients have been 

 named which may be employed by the few men who have 

 studied chemistry, to make effective dips at home at a less 

 cost than patent dips, but the ordinary farmer is strongly 

 recommended in his own pecuniary interest, as well as on 

 the score of humanity, not to attempt to combine materials 

 the nature of which he does not understand, but to use the 

 ready-made dips which experiment has shown to best suit 

 his purpose. The manufacture of sheep-dip is a complicated 

 technical process, which involves the application of wide 

 knowledge and experience to produce an article which will do 

 its work effectively and at the same time not injure the wool 

 or endanger the life of the sheep. 



The question as to what dips to avoid has been admir- 

 ably focussed in a brochure by S. B. Rollings, Calverley, near 

 Leeds. 1 He advocates the exclusive use of arsenic and 

 sulphur dips, stating, " arsenic has proved so effective, that at 

 least two-thirds of the entire arsenic production of the world 

 is used for insecticides." Quoting W. J. Austin, Norandoo, 

 Victoria, who as a test treated 10,000 sheep with a crude and 

 a prepared arsenical dip, he says : " The wool from the pre- 

 pared dip weighed an average of four ounces per fleece 

 heavier, and realised a halfpenny per Ib. more than the rest." 

 He adds : " Crude arsenical wools are harsh, and a bad 

 colour. Those with a prepared dip are brighter, softer, and 



1 Damaged Wool and its relation to Sheep-Dips, from the Bradford 

 standpoint. Bradford : William Byles & Sons, Printers, Piccadilly, 1903. 

 Price is. 



