462 



SCIENCE. 



[N. S. Vol. XI. No. 273. 



dairies in which neither good equipment 

 nor good intentions prevailed, but in which 

 ignorance and indifference combined to pro- 

 duce poor dairies and unwliolesome sup- 

 plies. The comparison between the results 

 of the determinations and the sanitary con- 

 dition of the dairies was plainly marked in 

 the photographic plates thrown upon the 

 screen. 



The practical importance of such an in- 

 vestigation Avas demonstrated in the publi- 

 cation of each year's results in the annual 

 reports. The public have given them se- 

 rious consideration and, in consequence, no 

 less than a dozen unworthy dairymen have 

 found their business unprofitable. In ad- 

 dition to this, several dairies have under- 

 gone a complete change in construction and 

 in methods of production, and the supply 

 as a whole had been raised to a high stand- 

 ard of purity. 



Notes on the effect of blood serum from tubercu- 

 lous animals and men on the tubercle bacillus 

 when mixed with it in the culture tube and 

 hanging drop : De. W. H. Park. 

 The serum was obtained through blisters 

 from twent5'-foar persons, twelve having 

 tuberculosis, and twelve not having any 

 sign of the disease. The tubercle bacilli 

 from a recent culture were ground up and 

 a fine watery emulsion made. To this 

 emulsion, divided into separate tubes, .was 

 added the serum from the different cases, 

 to an amount such that in each case a 10 

 per cent, solution of serum resulted. Al- 

 though in some the film forming on the 

 slanted tubes was more tenacious than in 

 others, no difference on the whole was seen 

 between the dilution of serum from tuber- 

 cular cases and that from non-tubercular 

 ones. The result on the whole did not seem 

 to offer much practical help. 



On the bacteriology of canned goods, with a de- 

 tailed account of bacteria detected in sour 

 corn : S. C. Pjsescott. 



The paper described some investigations 

 upon the bacteria present in preserved cans 

 of corn which had become spoiled and 

 ' swelled.' The cause of the trouble was 

 found to be the presence of certain spe- 

 cies of bacilli which resisted the tempera- 

 ture used in canning the corn. The same 

 bacilli were found upon the fresh corn and 

 husks. 



Experimental and statistical studies on the in- 

 fluence of cold upon the bacillus of typhoid 

 fever, and its distribution: W. T. Sedg- 

 wick and C. E. A. Winslow. (Eead by 

 Mr. Winslow.) 



A review of the literature on the subject 

 of ice-supply and the public health shows 

 that, while pollution of ice-ponds appears 

 to have caused intestinal disturbance, no 

 epidemic of typhoid fever has been satis- 

 factorily traced to such a source. While it 

 is known that cultures of the typhoid fever 

 germ are not sterilized, the important ques- 

 tion of the quantitative reduction of this 

 species by freezing has been studied in 

 only two limited investigations. The au- 

 thors have, therefore, frozen large num- 

 bers of tubes of water inoculated with four 

 different races of the typhoid bacillus, 

 and determined the reduction after vari- 

 ous periods. The results, twenty tubes 

 being averaged for each period, show a 

 rapid reduction in the first hour in freezing, 

 varying from 30 per cent, in one culture to 

 60 per cent, in another ; the reduction then 

 proceeds approximately with the time of 

 freezing, reaching a constant value of over 

 99 per cent, in two weeks. The last two or 

 three germs per thousand appear to be very 

 resistant, some remaining after twelve weeks 

 of freezing. The four races used show con- 

 stant individual differences in their suscep- 

 tibility to cold. Alternate freezing and 

 thawing was tested and found only slightly 

 more destructive than continuous freezing. 

 The destruction of the germ in cool, but 



