I S TI? .'1
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114
In operating, flasks, funnels and jars are put in thcir places: thcm thr solutions arc poured onto the filters, photo S o . 3 . The first parts of all the filtrates fall into tbe inclined guttei- and Aow into the receptacle. If thcrc bc a srries or samplcw it will be found t,liat by the time all the solutions are p u x d onto the
1:ie 3 .
filicrs, thc first one is filtering 1JPrfectly clear and is rrady to be transiwrcd to its jar, as shoirn in photo No. 4. 'The rack will be found convenient for another reason: Whcn fillinx the polarization tubes, the funnels are put buck into the corresponding holes in the funnel board, instead of being put on the jar previously mril, as is gener;ilI)- done. In this way thc solutions rcmain unaltcred. and can be used
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also from his statement in the third paragraph: "Glycerine has been used for saponification b u t m ~ e for r titers." If you will rcier to a lettcr written to you by lis, July IO, 1909, offering our cooperation to the Committee on Uniformity, you will find that we then enclosed you a copy of a method oi glycerine saponification Cor titers which we suggested could he published in the "Notes" if you considered it of sufkient iiiterest. The method was not published but in yrmur letter of July 1 7 , 1909, YOU stated that it and thc soap-stock method accornpanpin,q it would he considered by the Committee on Uniformity. Mr. Campbell, when chief chemist in 1900, first used the method for the titer test, adapting it from the LeHmann-Beam method of saponification for volatile fatty acid determination as given in Allen, 3rd edition, Voi. IT, Pt. I, page 61. This method has been in daily use in our laboratory continuously and exclusively about ten years, and during that time we have handed it on t o many others. Among these we may mention Mr. Oscar Wurster, chiei chemist, The M. Werk Soap Co., Cincinnati, O., Mr. Robt. E. Divine, consulting and analytical chemist, Detroit, and Mr. Wm. E. Garrigues, chemical engineer of Detroit in 1907. We have noticed no mention was made oi the method in the work on titcr tests done b y the Assoc. of Official Agricultural Chemists, Bureau of Chem., Bulletins 8 r and 90, and from this assume that the method has not been in general use. While we possibly may not claim t o be originators of the application of glyccrine saponification t o titer tests, yet as we seem to have used the method more and longer than any one of whom we know, and as the method as published seems to be worded as if new and original; it seems to us only just that the matter be placed in the proper light before the readers of THISJ O U R X A L . Yours respectfully, ARCHIBALD CAXFRELI.,
C . P. LONG.
Fig 4 .
again as a check, in case any doubt should arise about a reading on the polariscope. The size of the rack can be increased or decreased at convenience. The one shown in the photographs A'LFRDD KR.4FFT. has iroom for 1 2 samples. CHLIII'C*L
I.'\IIOX*TollY
~ Y A ~ L UA Ae ~ i c a ~ ~ u xco n i ,. Lin. w ~ , ~ ~o.,ilU. . , . ~'r., I(.
SAPONIFICATION OF FATS FOR TITER DETERMINATION.
Ediior of the Journal of I n d . alzd Eng. Chemistry: We notice the publication, in THISJ O U R N A L for N o vcmber, of an article in the "Notes" entitled "Rapid Saponification of Fats for Titer Determination,'' by C. V. Zoul, of the Proctor k Gamble Co., Cincinnati, 0. We are very glad to see this method published, as we have long felt it should have more publicity as it is very reliable, and most convenient. However, the article is worded so as t o lead a reader t o believe i t is new and original with Mr. Zoul, as can be inferred from the first paragraph of the article,
Fcb., 1 9 I I
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OP THE rrL"PE
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THE USE OF GLYCERINE IN SAPONIFYING FATS IN THE TITER TEST.
The following rapid method of saponifying fats for the determination of the titer has been worked out in this laboratory and is now being used for all titer determinations. Fifty cc. oi high-grade c. P. glycerine (97 per cent. glycerine) and twenty cc. concentrated caustic potash solution (roo grams XOH dissolved in roo cc. distilled water) are placed in a liter flask and warmed gently on an asbestos board over a low flame. When hot, fifty grams of the molten f a t are poured in and the flask rotated gently. Saponification begins at once and is soon complete, although there is usually some foaming before the mixture becomes clear. Complete saponification is shown by the mixture becoming periectly clear and homogeneous. When saponification is complete the flame is removed and
