PROFESSOR DELEPINES EXPERIMENTS 



137 



able from various sources, to show that the pathogenicity or viru- 

 lence of milk is increased by rise of temperature. Many workers 

 have made reference to this matter in its relation to the toxicity 

 of milk, cream, butter, and ice-cream in hot weather. Recently, 

 Delepine of Manchester prepared three tables which well illustrate 

 the point.^ He found that mixed milk coming from a distance of 

 more than 40 miles, and generally kept for from twent}'-four to 

 sixty hours or longer, showed an increase of virulence on inocula- 

 tion into guinea-pigs in proportion to the mean temperature in the 

 shade in Manchester during the time the specimens were kept 

 (tuberculous samples excluded) : — 



Mixed milks coming from a short distance (generally under 

 20 miles), most of them kept for less than ten hours (with the 

 exception of five out of the seven bad specimens, and four out of 

 the twenty-two good specimens, which had been kept somewhat 

 longer), gave a similar result (tuberculous samples excluded) : — 



Mean Temperature in the 



Shade (Manchester) 



during Time the Specimens 



were kept. 



Specimens 

 producing 

 no Noxious 



Effects. 



Noxious 

 Specimens. 



Totals. 



Percentage 



of Good 

 Specimens. 



I 



8 

 II 



2 



I 

 9 



15 



29 



^ Jour, of Hygiene, 1903, vol. iii., No. i, p. 83. 



1000 

 88-8 

 73'J 



50-0 



75-63 



