Evening Republican, Volume 19, Number 132, Rensselaer, Jasper County, 4 June 1915 — Field Test for Dipping Bathe [ARTICLE]

Field Test for Dipping Bathe

A practical field test tor lime-sulphur dipping baths for live stock has been devised by scientists in the government department to lessen the difficulty experienced in maintaining these baths at the standard strength. The new test wta be of use not only to the federal and state authorities concerned with the supervision of official dippings, but also to private persons whq wish to test the strength of their preparations. The new method, It is pointed out, is Intended for field use only and can never take the -place of the more accurate laboratory analysis. Standard iodin solution is added to a measured quantity of the bath until all the calcium polysulphid in the latter has been decomposed. In this way the Quantity of <odin required serves to measure the amount of calcium present as polysulphids and thus, with sufficient accuracy for field use, the amount of sulphid sulphur. The complete decomposition of the oalcium polysulphid is indicated by the failure of the bath liquid to color when a dilute alkaline solution of sodium nltroprussid is added. No technical knowledge, however, is required to make the test. Each cubic centimeter of the test finld employed in its operation represents one-tenfh of 1 per cent sulphid sulphur in the bath. A description of the necessary apparatus and directions for operating are published in a new bulletin (Na 163) of the department, “A Field Test for Lime-Sulphur Dipping Baths." The -bulletin also contains tables which will guide anyone,, in bringing the dips up to the strength required by official regulations. In dipping baths for sheep these call tor 1.5 per cent of sulphid sulphur and for cattle 2 per cent.