CHEMISTRY. 



119 



Although tho bacillo-coccus obstinately 

 -row in gelatin when inoculated 

 in Ihe-e dilute media, it produces acharaeler- 

 ic though slow growth in broth. Nitrification 

 > nnliiri-il iii ammoiiiacal solutions !>y in- 

 ulating from Mich broth cultivation-. 

 Chemistry of Foods. When milk is ster- 

 by heating in loosely plugged flasks im- 

 ti'iiin bath, su rface evaporation does 

 ir, and little or no pellicle is formed on 

 face. l>r. A. H. Leeds has found that the 

 ices in the behavior of raw, boiled, and 

 erilixed milk when treated with dilute acid 

 t as striking as had been anticipated. 

 t when ordinary raw milk was diluted with 20 

 ,es its volume of water and the precipitate 

 filtered off, the dilute acid filtrate gave on 

 iling an additional precipitate. Milk which 

 been heated for an hour (sterilized) or 

 iled for half an hour behaved differently. It 

 ve a larger amount of precipitate with dilute 

 id. but yielded no further precipitate on boil- 

 ing the filtrate. Plate cultures of Swiss con- 

 milk showed it to be entirely sterile, no 

 rial colonies appearing in it when the plates 

 re kept several days. Polariseopic determina- 

 ns were made of the amount of milk-sugar 

 ut after each heating; the raw milk con- 

 incd 4*18 per cent. No change could be per- 

 ceived till the end of six hours in the steam 

 hath, when the sterilized milk had become 

 strongly brownish yellow, like an infusion of 

 coffee to which a large amount of milk had been 

 added, and the percentage of milk-sugar had 

 fallen to 3'94. It then steadily diminished until 

 the end of forty-eight hours the milk-sugar had 

 ppeaivd. The process of heating to prepare 

 e sterilized condensed milks of commerce is 

 t carried far enough to lower perceptibly their 

 rcentago of milk-sugar. This is shown by 

 analysis of both an American and a Swiss 

 reparation, concerning which it is remarked 

 h:'t the composition of the two milks is sur- 

 prisingly similar when we consider that the cat- 

 tle fed on the Swiss Alps and in the West 

 ern State from which the American sample 

 cam.' were of different breed, and that their 

 feeding, care, etc., were also widely diverse. 

 Condensed milk properly prepared is, in fact, 

 sterilized milk in a concentrated, convenient, 

 and portable form. It is important to compare 

 with sterilixed milk, prepared and sold in 

 rilixed flasks, but, without condensation, 

 mples of a particular brand of sterilized milk 

 tained in midsummer exhibited a separation 

 fats iu mas-cs of considerable size. By mod- 

 erate wanning and shaking this fat could bo par- 

 tially diffused through the milk, but not in such 

 a manner as to bring the sterilized milk back to 

 the appearance of ordinary milk, or of milk 

 on which the cream has risen on standing and 

 then has been shaken up again with the milk. 

 Samples obtained in December did not exhibit 

 this appearance, but resembled rich milk; and 

 the separation of the fat in the former case was 

 probably due to the samples having been kept 

 for some time in the laboratory. The most 

 striking feature of the samples was their high 

 percentage of solids. The author is of the 

 opinion that the period of one hour usually 

 recommended for keeping milk at the tempera- 



ture of boiling water in order to sterilize it it 

 xoesfivc. Experiment! have shown that iii the 

 majority of caj.es the sterilization is complete in 

 half an hour or le.-s time. 



An albumose and a ptomaine have been iso- 

 lated by K. A. von Scnweinitz from the prod- 

 ucts severally of the germs of the- hog cholera 

 and the swine plague. The names auchololoxin 

 and sucholoalbumin have been given to the sub- 

 stances derived from the hng-t-lmleru cultures, 

 and suplagatoxin and wplayoalbumin to those 

 dt rived from the swine-plague cultures. A subcu- 

 taneous injection of a smallquantity of these sub- 

 stances is sufficient to produce death in guinea- 

 pigs in from twenty-four to forty-eight hours. 

 If, however, a much smaller quantity is injected 

 and the injection is repeated a number of times, 

 the animals are protected from the correspond- 

 ing disease when communicated by direct inocu- 

 lat ii >n with the germ. The author and Dr. W. H. 

 Gray have also produced great resistance and sub- 

 sequently immunity from diphtheria in guinea- 

 pigs by first treating them with the chemical 

 products obtained from cultures with the germ. 



Two persons in Mansfield, Ohio, having been 

 made sick by eating pie made from canned pump- 

 kin, the attending physician pronounced the case 

 one of lead poisoning. A specimen of the canned 

 pumpkin was examined by Prof. H. A. Weber, 

 who found that it contained an amount of stan- 

 nous salts equivalent to G'4 maximum and 51-4 

 minimum doses of stannous chloride per pound. 

 Another can from the same lot contained tin 

 salts equivalent to 7 maximum and 56 minimum 

 doses of stannous chloride per pound. The un- 

 expected large amount of tin salts in such an in- 

 sipid article as canned pumpkin, and the ill ef- 

 fects of the consumption of the viand, suggested 

 the advisability of extending the investigation 

 to other canned goods in common use. A line 

 of articles was purchased in open market as sold 

 to consumers, no pains being taken to procure 

 old samples. The collection embraced fruits, 

 vegetables, fish, and condensed milk. Except 

 the condensed milk, every article examined was 

 contaminated with salts of tin. In most cases 

 the amount present was so large that there could 

 be no doubt of danger to health from the con- 

 sumption of the food. 



The experiments of Dr. J. H. Garrett as de- 

 scribed in his book on "The Action of Water on 

 Lead," show that if a water is fairly pure it will 

 act upon lead or dissolve it to a certain extent, 

 even if no acid is present. The author observed 

 that distilled waters that are neutral or even very 

 faintly alkaline can act upon lead. The lead, it 

 seems, derives the oxygen necessary for its cor- 

 rosion, not so much from the free oxygen or any 

 other oxygenous gas existing in solution in the 

 water, as from ni* rates and nitrites present. The 

 quantity requisite for action, at least in the ab- 

 sence of anv alkaline-earthy carbonates, is ex- 

 tremely small. Its origin may be sought " in the 

 decomposition of the organic matter which such 

 waters invariably contain." 



A new method proposed by Raoul Bnill6 for 

 detecting olive oil and seed o(l in natural butters 

 and oleomargarine depends on the changes of 

 color produced by contact with solution of silver 

 nitrate in ethylic alcohol. Olive oils sooner or 

 later take a fine green color, which is lighter in 





