16 BULLETIN 451, U. S. DEPARTMENT OF AGRICULTURE. 



The finished solution, drawn off from the sediment, should theo- 

 retically contain 18 per cent (grams per 100 c. c.) of sulphid sulphur, 

 but probably will contain somewhat less. It is, therefore, appro- 

 priate for dipping sheep at a dilution of 1 volume of concentrate to 

 9 or 10 volumes of water, and for cattle at a dilution of 1 volume of 

 concentrate to 7 or 8 volumes of water. But in any event, since 

 baths lose strength during dipping, it is very desirable to keep them 

 at all times under control by means of a " field test." 10 



The particular advantages of the above formula are, first, that it 

 closely approaches the theoretical ratio, making allowance for im- 

 purities; second, it is as concentrated a product as can be prepared 

 without conversion of thiosulphate to sulphite ; and third, the figures 

 are easily remembered and readily converted into the quantities of 

 ingredients necessary to prepare a batch of any desired size. 



In deducing a formula for the preparation of highly concentrated 

 proprietary solutions it is evident that the manufacturer must make 

 a few trial runs with plenty of sulphur in order to establish the 

 conditions which will uniformly yield the product he desires, analysis 

 of which will then inform him by how much he may safely reduce 

 the sulphur to allow for the formation of sulphite. 



REFERENCES TO LITERATURE. 



1. Chapin, Robert Macearlane. Some new methods for the analysis of lime- 



sulphur solutions. Jrn. ind. and eng. chem., v. 8, no. 2, p. 151. New 

 York, Feb., 1916. 



2. Chapin, Robert Macfarlane. New methods for the analysis of lime-sulphur 



solutions, II. The estimation of poly-sulphur. Jrn. ind. and eng. chem., 

 v. 8, no. 4, p. 339. New York, April, 1916. 



3. Lindet, L. and Brasart. Sur l'emploi des phenols au dosage des alcalino- 



terreux. Application au controle des laits de chaux in sucrerie. Bul- 

 letin Assoc, chim. sucr. et dist., t. 27, no. 10, p. 933-936. Paris, April, 

 1910. Abst. in Jrn. Soc. chem. ind., v. 29, no. 10, p. 643. London, May 

 31, 1910. 



4. Dtvers, Edward, and Shimidzu, Tetstjkichi. On calcium hydrosulphides. 



Jrn. Chem. soc, v. 45, p. 270-291. London, 1SS4. 



5. Van Slyke, L. L., Hedges, C. C, and Bosworth, A. W. A chemical study of 



the lime-sulphur wash. New York Agr. exp. sta., Bui. 319, p. 3S3-418. 

 Geneva, Dec, 1909. 



6. Kuster, F. W., and Heberlein, Editard. Beitriige zur Kenntnis der Poly- 



sulfide. Ztschr. anorg. chem., Bd. 43, Heft 1, p. 53-S4, Jan. 16; Bd. 44. 

 Heft 4, p. 431-452, April 4. Leipzig, 1905. 



7. Haywood, J. K. The lime-sulphur-salt wash and its substitutes. U. S. Dept. 



Agr., Bur. Chem., Bui. 101. 29 p., Washington, 1907. 



8. Auld, Samuel James Manson. The reaction between calcium hydroxide and 



sulphur in aqueous solution. Jrn. Chem. soc, v. 107 & 108, no. 630, 

 p. 480-495. London, April, 1915. 



9. Imes, Marion. Sheep scab. U. S. Dept. Agr., Farmers' Bui. 713. 36 pp. 



Washington, 1916. 



10. Chapin, Robert M. A field test for lime-sulphur dipping baths. U. S. Dept. 



Agr., Bui. 163. 7 pp. Washington. 1915. 



WASHINGTON : .GOVERNMENT PRINTING OFFICE : 191& 



