1890.] MICKOSCOPICAL JOURKAL. 213 



We regret that we cannot reproduce the paper in full. 



A Parasitic Amoeba, hitherto known to be found only in Russia 

 and Egypt, was found by Dr. Osier, of Baltimore, in the pus from a 

 liver abscess and in the faeces in a case of chronic dysentery. The 

 patient had lived for five years in Panama. The amoebae had about 

 twelve times the volume of the white blood corpuscle, and were very 

 active in their movements. — Centralblatt fur Bakter. und Parasit. 



The Hydrophobia Bacillus. — At the late annual meeting of the 

 American Neurological Association in Philadelphia, Dr. Richard Mol- 

 lenhauer exhibited some microscopic specimens taken from a dog 

 which he had succeeded in rendering rabid by inoculation. The germ 

 was a bacillus whose various growth-stages presented a uniform type. 

 In its adult period it was usually found in chains typically made up of 

 four, rarely of three, somewhat more frequently of two, and exception- 

 ally of five links. — Sanitary Era. 



Sulphurous Disinfection. — Dr. Henry B. Baker writing to E. B. 

 Frazer, M. D., Secretary of the Del. State Board of Health, says: 



Your letter acknowledging the receipt of a copy of my letter to Dr. 

 Dufiield (giving results of experience of health officers in Michigan, 

 and an account of the experiments by Pasteur, Roux, Dujardin-Beau- 

 metz, and others relative to sulphurous disinfection) is before me. 

 You ask me for further opinion, and refer to the report of the Maine 

 State Board of Health for 1889, page 251, and Dr. Mitchell Prudden's 

 estimate of the want of value of sulphurous disinfection. 



There are at least two valid objections to the acceptance of Dr. Prud- 

 den's conclusions to which you refer : (i) His experiments dealt with 

 a micro-organism which seems to be difierent from the one most gen- 

 erally accepted as the probable cause of diphtheria. Therefore he may 

 or may not have been dealing with a micro-organism causing diph- 

 theria. (2) The quantity of sulphur burned ; the strength of the sul- 

 phurous acid fumes which he employed is not stated. It having been 

 proved by actual experience with disease and by other laboratory ex- 

 perimenters (Pasteur, Roux, Dujardin-Beaumetz, Vallin, Legouest, 

 PoUi, Pettenkofer, Dougall, Fatio, Pietra Santa) that sulphurous acid 

 gas is fiot always a disinfectant when employed in small proportions, 

 and that it is a disinfectant when employed in large proportions, such 

 as result from the burning of three pounds of sulphur to each thousand 

 cubic feet of air-space, no different conclusion should be reached from 

 Doctor Prudden's experiments as published. 



You mention that Dr. W. H. Welch of Baltimore, " enters his pro- 

 test " against disinfection by sulphurous acid gas. I respectfully sub- 

 mit that entering a protest should count for very little in science as 

 against results of actual practical experience in the restriction of diph- 

 theria ; it should not even take rank with definite statements of results 

 of laboratory experiments. 



Laboratory experiments are very valuable, but they need to be re- 

 peated, by the same observer and by other observers, in order to elim- 

 inate errors due to accidental and incidental conditions. 



It is not easy to make laboratory experiments which shall conform 

 to or correctly represent average conditions in actual outbreaks of dis- 

 ease. That is probably one reason for the discrepancies in laboratory 

 experiments, and for the disagreement of some laboratory experiments 



