!MIS
Val. 17, 30.'3
I.\~IIt~~YTMA I, :I:VD ICNGINBBfil.\'(~ CXE.VISTI1Y
tairied fur t.lic mixed free fatty acids done show, as expected. a straady gain in the rate of molecular wcight inrrease. Work in Progress 'J%I! h e r v a t i o n s mentioned naturally lod to a study of the lwliiiyior of tlie individual pure acids and of piire glycerides
surb NS that o i linolenic acid. Tliis work is iii progren-; at this time. Oleic acid, as expected, sliowcd a low rate of molecular weight increase at 205" C . A little preliminary work Iias been done on linolenic acid The resuks obtained with other solvents such as acetic acid. rampbiir, and ethylene dibromide osi boilings with littneerl and China wood oils, are also being compared.
Rapid Determination of Phosphorus in Bronze' Method Ive oix- grain of sample in 5 c r . of l i y d r d ~ l ~ x acid iv c gravity 1.20) and 10 ec. of 1 : 1 nitric acid. Iioii t.o drive off brinvii fumes and then wilsli down tlie iiisidr of the beaker with warm water. The total voliiirie of the , d o tion should be about 40 cc. Cool to .iO"C.,then add 25 cc. o i dear molybdate solution und stir iint,il a precipitate forins. Transfer to a Goetz tribe iising as l i t t l e water as possihle. TIE total d u m e of tho sohition in thr tiil)e oiight not to exw e d 75 co. Twirl for 5 Ininrtt,es at 1300 r. 1). m. Ibmove from t.lie shield and read pliosphorrrs iwntrrlt (IirPrt. Each division equals 0.01 per w i l t ptiasphoriis.
Notes Solutions that are too warm (100- C.) or too a c i d niav t h r o w out molybdic acid and cause high results. The solution of the sample must be clcar ( d l tin in solution) before adding the molybdate solution. Check solution anti apparatus with a standnrd samolc of ohosuhor bronze. .The E?ure& ol Standards has a phosphor bronze standard sample, No. 63. The method is applirvhlc to material containiiig 0.4 per cent of ,,hosphorus, por sam. FIRure Z--Tuhrs and Iiolder. Note Precipitate in End of Tubes i,lcs hkher than this use i~ropuriionatclysmaiter charges. The tubes must be perfectly clean and free from oil or dirt: otherwise the precipitate will stick to the sides of the tubes. .4rnmonia nil1 dissolvc the piecipitati. thns permitting quick clcaning.
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B ~ i r c i i i of i Stitndiirdi phosphor 1bio1111. s $ z n i A No. 88.
Mine Rescue Contest Amouoced--The Bureau oi Mines will :onduct the fourth international contest in first aid and mine I C S C ~ I Pwork at Sprinpfield, 111.. September 10 to 12, 1925.
