526 FOODS AND FOOD ADULTERANTS. 



CERTIFICATE OF 1'ROV. PLYMMON S. HAYES.* 



CHICAGO, June 29, 1883. 



On the 9th day of Jnue, 1883. I received three samples of ]ard from Prof. W. S. 

 Haines, marked, respectively "No. 1 Fowler," "No. 2 Fowler," and " No. 3 Fowler." 

 These samples of lard I examined microscopically, after having crystallized tho stear- 

 ine found in the samples from solution, and was not able to detect any beef steariue 

 whatever. 



PLYMMON S. HAYES. 



Professor Hayes adds the following observations : t 



He has examined crystals which he obtained by dissolving the stearine of beef 

 tallow, of mutton tallow, and of lard three samples in absolute alcohol; the sub- 

 stances were dissolved and crystallized, redissolved and recrystallizcd, and finally 

 the alcohol was evaporated off; he considered those the crystals of pure stearine ; he 

 has never examined the crystals of pure palmitiue to his knowledge ; he does not 

 know what, if any, difference there may bo between tho crystals from pure stearine 

 and pure palmitiue; he does not think tho appearance of the crystals obtaiued by 

 himself depend entirely upon the relative proportions of steariue and palmitiu in 

 the specimens; the crystals from a fat, consisting of oleiuc, stearine, and palinitioe, 

 which has been warmed and then slowly cooled, would be those of stearine and pal- 

 mitine, probably more or less modified, as one or the other was in excess, and also 

 by the presence of the oleiue. Molten lard is a solution of oleine, steariue, and pal- 

 mitiue. When this is allowed to cool slowly aud crystallize the crystals are value- 

 less, for tho reason that they give no distinctive difference when examined plainly 

 or by means of the polariscope. He has examined crystals in the manner de- 

 scribed by Mr. Hoskins ; he will not say Mr. Hoskius's method is'wrong, either in prin- 

 ciple or in application, but it does not produce results that are plainly marked. He 

 pursued that process for over two weeks before he abandoned it as useless. In his 

 examinations by that method he took the sample to be examined and put it on a 

 microscopic slide, put a cover-glass ov>er it, and applied heat until it was thoroughly 

 melted, aud then set it aside to cool; sometimes heallowed itto cool very slowly, and 

 sometimes ho cooled it by means of a cooling apparatus; in neither case did he get 

 satisfactory crystals ; he never tried cooling it by means of a hot iron allowed to 

 cool slowly with the lard. 



CERTIFICATE OF DR. I. N. DANFORTH.J 



CHICAGO, June -211, 1883. 



I hereby certify that on the 8th day of June, 1883, I received from the hands of 

 Prof. Walter S. Haines, of Chicago, three specimens of lard, numbered 1, 2, and 3, re- 

 spectively, aud said to have been manufactured by the "Anglo-American Packing 

 and Provision Company," of Chicago ; that I was requested by said Haines to ex- 

 amine said specimens microscopically, and state my opinion as to their purity or im- 

 purity ; that I have examined said specimens as thoroughly and carefully as the time 

 allowed would permit, aud am of opinion that they are composed entirely of the fat of 

 the hog. 



ISAAC N. DANFORTH. 



Dr. Danfortb. in explanation said : 



Ho lias examined the crystals of pure stearine; ho procured the lirst specimen from 

 Professor Haiues, aud afterwards prepared specimens by methods used by chrmists ; 

 ho has not examined the crystals of pure palmitino ; he does not understand th;i( any 



* Op. cit., p. 179. t Op. cit., p. 182. 



iOp. cit., pp. 179,180. $ Op. <!(., p. 184. 



