521 FOODS AND FOOD ADULTERANTS. 



ucnt parts of lard arc oleme, palmitiuo aud steanuc; the crystals of steariue seem to 

 be modified according as the substance is mixed with beet'stearine, or hog stearine; 

 his answers are in part from the books and in part from his own experience; he has 

 never had the opportunity of observing any modifications in the crystals by an in- 

 crease or diminution of the palinitine in a specimen, and consequently can not say 

 whether or not the crystals would be modified as stearine or palmitine predominated. 

 In applying the method of microscopical examination to lard, described by Mr. Hos- 

 kins, he takes a microscopical elide and cleans it, chemically, theu puts on the elide a 

 small quantity of the specimen to be examined, puts it in a water-bath, at the tem- 

 perature of boiling water, covers it with a covering glass and allows it to cool as 

 slowly as possible; he has made a number of experiments of this kind, sufficient to 

 satisfy him that be could find no distinction. The method be used, and upon which 

 his conclusions as to the lard in question in this case are based, was as follows : He 

 dissolved the specimens in sulphuric ether, allowed the ether to partially aud slowly 

 evaporate and crystals to deposit, then decanted the remainder of the ether, washed 

 with ether and decanted again, then treated with absolute alcohol ; after which the 

 crystals were examined under the microscope. 



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Commercial steariue may or may not include palmitine, according as heat and 

 pressure are used in the separation ; ho thinks ho understands the manufacture of 

 commercial stearine; it would depend upon the temperature to which it is subjected 

 whether it would contain all the original parts of the fat, except what oleine may 

 have been pressed out; palmitine is said to liquify at a temperature of 45 C. 

 consequently if the fat material is subjected, at that temperature, to a pressure 

 similar to that used for extracting the oleine, the palmitiue would also be forced 

 out ; he does not know, as commercial stearine is usually made, that it is ever 

 subjected to a temperature high enough to press out the palmitiue, but he has seen 

 it subjected to a temperature in the manufacture of candles obtaining stearic 

 acid when it certainly would be pressed out ; as to whether the crystals produced 

 from commercial steariue would be the same as those produced from what has been 

 called by other witnesses chemical stearine, he can only say that he is not acquainted 

 with the peculiar characteristic features of palmitic crystals; the size and genera; 

 character of the crystals depends on the temperature and slowness of evaporation; 

 there is a ditference between the crystals of pure steariue from lard and that from 

 tallow; he states this upon the theory that the steariue he has obtained was pure 

 steariue, but inasmuch as he is not sure that the stearine he obtained did not con- 

 tain a mixture of palmitine, he desires to make that qualification. As between the 

 crystals obtained by his process aud those that caused the so called grain of the lard, 

 he could not, chemically, see any distinction whatever; microscopically this grain 

 seems to be the crystal, in a form very much resembling an ordinary roadside bur, when 

 examined under the microscope, but the details are so ill-defined that it is simply im- 

 possible to make any differentiation ; the crystal itself would be a solution, if melted. 

 He does not think crystals obtained from lard itself, without extracting the oleine, 

 would be as. valuable as those from the steariue, because it is acknowledged that 

 that there is at least 60 per cent, of oleine in the lard, and that GO per cent, of extra- 

 neous matter would, he thinks, necessarily render the crystals more difficult to dif- 

 ferentiate than if crystallized from the stearino alone ; probably the crystals which 

 characterize the grain of the lard are the same as those obtained by the method de- 

 scribed by Mr. Hoskins ; they might be the same thing, but yet so modified by the 

 influence of the oleine, that the peculiarities of the crystals would be less prominent ; 

 they would be more or less stunted, or their development favored. As to whether or 

 not the method requiring the least manipulation would bo likely to give the best re- 

 sults would depend entirely upon the advantages gained by the manipulation, and 

 the care with which it is done. In transferring the crystals to the microscope. In- 

 takes a small glass tube a pipette cutting off for eacli observation, with a die, the 

 piece used in the previous case, so that it is perfectly clean as it goes into tho liquid ; 



