454 



SCIENCE. 



[Vol. V., No. 122. 



Mr. R. A. Proctor attempts to explain 

 how earthquakes are caused, in the June 

 number of Harper's magazine, and attributes 

 their energy to the action of interior heat on 

 percolating water, and their opportunity to the 

 time of changing pressures caused by atmos- 

 pheric or tidal loading and unloading of the 

 sensitive crust of the earth. Formidable num- 

 bers represent the tons of air or water brought 

 on or taken off certain parts of the earth's 

 surface in the passage of cyclones and anti- 

 cyclones, and in the rise and fall of tides : but 

 it may be strongly questioned whether these 

 changes of pressure are very effective in deter- 

 mining the time of earthquake snaps ; for the 

 changes are gradual and short-lived, the press- 

 ures are relatively light, and the surfaces on 

 which they have effect are so broad that the 

 extremely small deformation needed for ad- 

 justment of equilibrium might be produced 

 without an}' cracking or snapping. The omis- 

 sion of clear reference to orogenic earthquakes 

 in such an article is very unfortunate, for Mr. 

 Proctor will have many readers who take him 

 for an authority on such matters ; and, in the 

 present attitude of seismolog} T , the orogenic 

 theory is certainly strongly supported hy those 

 who give the stud}' the closest attention. It is 

 rather remarkable to find no reference to grav- 

 itative distortions of the earth's crust, except 

 in explaining the heat of the interior, after 

 Mallet's method, and no mention of earth- 

 quakes following the making of cracks that 

 ;are freely assumed as the passages by which 

 water enters the subterranean regions, there to 

 be exploded into steam. 



LETTERS TO THE EDITOR. 



*** Correspondents are requested to be as brief as possible. The 

 writer's name is in all cases required as proof of good faith. 



Real and imaginary Americanisms. 



In the verbatim report of Sir William Thomson's 

 famous Baltimore lectures occurs the expression, 

 " and that is why I cannot get the electromagnetic 

 theory." To this, Mr. George Forbes, in his com- 

 mentary in Nature for April 30, appends a footnote: 

 "These reports are generally quite verbatim; but I 

 am sure Sir William Thomson is not responsible for 

 this characteristic Americanism." Is it not, rather, 

 a Scotticism? It is no Americanism at all. Although 



an American of long standing and considerable ob- 

 servation in such matters, I never heard ' get ' by 

 itself used in the sense of ' comprehend ' or ' under- 

 stand.' To 'get hold of,' is a not uncommon collo- 

 quial form. But in the same paragraph Mr. Forbes 

 passes unnoticed a real and most prevalent Ameri- 

 canism: 'I do not think I would like to suggest,' etc. 

 And again, at the close of the lectures: " I would be 

 most happy to look forward to another conference." 

 This substitution of ' would ' for ' should ' we should 

 charge to the reporter, and feel sure that he was born 

 west of New England and New York, where the 

 just distinction between 'will' and 'shall,' 'would' 

 and ' should,' is innate, while it is lost farther west 

 and south. But the confusion is reaching England, 

 as some recent books and newspapers show. I do 

 not believe that Sir William Thomson has caught the 

 prevalent epidemic, much as he has been in the 

 affected districts. A. G. 



The cholera bacillus. 



The exact role of the ' comma bacillus ' in the eti- 

 ology of cholera Asiatica remains unsettled. Argu- 

 ments for and against the conclusions of Koch are 

 perhaps equally strong on both sides, as evidenced 

 by the discussions in the conferences on cholera held 

 in Berlin, Munich, and London. Inoculation which 

 completes the chain of evidence required to make 

 good Koch's case, has in his hands, and in those of Ni- 

 cati, Rietsch, Ermengen, Babes, and Watson Cheyne, 

 produced positive results. Dr. Crookshank of King's 

 college hospital, London, who has been working in 

 the bacteriological laboratory here, and to whom I 

 am indebted for the accompanying drawings, tells me 

 that in Babes' s cases three guinea-pigs, out of six 



Fig. l. 



Section of intestine in cholera showing Koch's 

 bacilli in the superficial layers. 



inoculated in the duodenum, presented the lesions of 

 cholera; and pure cultivations of the bacillus of Koch 

 were obtained from the intestinal contents. Koch 

 has just introduced a new method of operation with- 

 out the production of any external lesion, and he 

 reports the cases as completely confirming the view 

 of the pathogenic nature of the bacillus. Klein and 

 Gibbs have denied the existence of the cholera bacil- 

 lus in the intestinal tissue. On the other hand, since 

 Koch's original proof, they have been demonstrated 

 by Babes, and confirmed by Crookshank, by staining 

 the sections after the method introduced by Babes 

 (vide figure). This consists in cutting very thin sec- 

 tions in close proximity to a Peyer's patch, placing it 

 in an aqueous solution of good fuchsin for twenty- 

 four hours, washing in a sublimate solution (1-1000), 



