40 Journal of the Deparpmbnt of Agriculture. 



THE USE OF HARD OR SALINE WATERS FOR 

 SHEEP DIPPING. 



By Dr. Chas. F. Jueitz, M.A., F.I.C., AgTiciiltural Research 



Chemist. 



About ten years ago representatious were made to me regarding' the 

 difficulty experienced by farmers in certain districts in securing a 

 uniform dippiug fluid when mixing the natural waters of those 

 distiicts with well-known proprietary sheep and cattle dips. A few 

 tests were subsequently made in the laboratories of the Cape Depart- 

 ment of Agriculture, then under my charge, and the indications at 

 the time pointed to the desirability of a more extensive investigation 

 of the subject. Recently the subject again came before my notice, 

 and, under the circumstances, it may serve a useful purpose to record 

 some details of the tests above alluded to. 



Early in 1909 the Magistrate of Calvinia wrote to the Depart- 

 ment commenting on the failure of dipping operations to eradicate 

 scab, and suggesting that this failure might be due to the insolubility 

 of the dipping materials in the waters of the district. jS^o analysis 

 of those waters had up to that date been made in the Cape laboratories, 

 but it appeared likely that they would be found to contain lime and 

 magnesia salts, and the suggestion was accordingly made by me thai 

 an investigation be made with a view to ascertain whether such brak 

 waters diminish or prevent the solubility of carbolic dips, in respect 

 of which it seemed probable that their action would be chiefly 

 manifested. At the same time I proposed to test the effect on 

 sodium arsenite and on lime and sulphur dips. The last iiamed, I 

 considered, would present the least difficulty with brak waters. The 

 plan was to procure three or four gallons of brak water from different 

 sources and to make a chemical analysis of each ; also to test the 

 dissolving effect (a) of the brak waters, and (h) of pure distilled 

 water, by shaking each up separately with sodium arsenite in the 

 proportion of 5.4 grammes of the arsenite to 1 litre of water, i.e. in 

 the proportion (5 lb. per 100 gallons) recommended for practical 

 dipping operations. 



In October, 1909, it was reported that waters on the farms 

 Biesjesvlakte and Roodeklipheuvel, in Area II, Clanwilliam Division, 

 would not mix either with Cooper's dip or with carbolic dips. Two 

 samples of water were accordingly procured from the farms mentioned. 



