1909.] The Electrical Readtions of certain Bacteria, etc. 



321 



(2) They were present in larger numbers than would have been obtained 

 in 2 or 3 minims of the original urine. 



(3) The transmission of the bacilli by the current is emphasised by the 

 relatively large number of bacilli obtained in the trap when working with 

 very much diluted solutions of the original urine. 



(4) The evidence is not complete that all the bacilli present in the urine 

 used were conveyed into the trap (though examinations of the " catch " were 

 made at successive stages of the electrolysis). 



The appearance of the bacilli in the films made from the trap is similar to 

 that in a film from centrifuged urine, though the pus cells undergo 

 dissolution with increasing alkalinity of the trap contents. If the electro- 

 lysis was carried on for 24 to 36 hours the bacilli failed to take the stain 

 properly ; such exposure, however, is unnecessary. 



I am indebted to Mr. S. Kuss, Demonstrator of Physics, Manchester- 

 University, for assistance with the electrical technique and measurements ; 

 to Dr. Eastes for the use of his laboratory during the earlier part of the 

 experimental work, and to Mr. Pardoe for tuberculous urine from St. Peter's 

 Hospital. 



In conclusion, the results of the present preliminary investigation may be 

 summarised as follows : — 



Certain bacteria under the influence of a suitable current aggregate at one 

 or other electrode. The aggregation varies with the nature of the 

 electrolyte, and is probably due to affinity between the products of 

 electrolysis and the bacteria. It occurs with killed as well as with living 

 bacteria. The aggregation by electrical currents affords a means of 

 collection and examination. The differences in behaviour of various 

 bacteria are such as to suggest the possibility of utilising the method for 

 purposes of specific discrimination ; but in this particular the data hitherto 

 obtained are not sufficient to warrant definite statements. 



List of Electrolytes in vjhich Reaction of Tubercle Bacilli was sought. 



Inorganic. — Potassium iodide, iodic acid, sodium sulphite, sodium carbonate, 

 sodium bicarbonate, sodium nitrite, ammonium magnesium phosphate, 

 potassium chlorate, microcosmic salt, ammonium magnesium sulphate, 

 potassium cyanide, and copper sulphate. 



Organic. — Sodium tartrate, sodium acetate, sodium citrate, maltose, 

 glucose, lactose, cane sugar, ethyl alcohol, methyl alcohol, acet-aldehyde, 

 glycerin, formalin, formic acid, amido-acetic acid, urea, uric acid, sodium 

 urate, oxalic acid, urea nitrate, lactic acid, acetone, chloral hydrate, 



VOL. LXXXI. — B. 2 A 



