7 i6 



THE POPULAR SCIENCE MONTHLY. 



ful. Sir Henry Roscoe moved a vote of 

 thanks to M. Moissan and M. Meslans. The 

 vote, he said, must be regarded as coming 

 from the whole Association and not simply 

 from the Chemical Section. Prof. T. E. 

 Thorpe seconded the motion, which was car- 

 ried with loud cheers, and the president of 

 the section, Dr. Emerson Reynolds, sent a 

 telegram to M. Moissan congratulating him, 

 on behalf of the section, on the great success 

 of the demonstration. 



Bacteriology in Chemistry. Bacteriol- 

 ogy, said Prof. Frankland, opening the dis- 

 cussion of that subject in the British Asso- 

 ciation, although originally an offshoot of 

 botany, received its great impulse from the 

 association with chemistry which began 

 with the researches of Pasteur, while the 

 greater part of our more recent knowledge 

 was due to the labors of those medical men 

 who had followed in the steps of Koch and 

 his pupils. The progress that has been 

 made of late years in this line of research 

 was mainly due to the methods of producing 

 pure and selective cultivations. These meth- 

 ods did not at present seem capable of any 

 great modification, and a knowledge of them 

 might be regarded as essential in a really 

 liberal education. Pure cultivations of 

 yeasts were now articles of commerce, and 

 pure cultivations of microbes for purposes of 

 research could be obtained in the same man- 

 ner as pure chemicals. Bacteria, whose 

 properties had been modified by successive 

 cultivations, are also supplied in quantities 

 for the preventive inoculation of cattle. 

 Later work had shown that the differentia- 

 tion of even the most carefully studied bac- 

 teria, such as those of cholera and typhoid, 

 was very difficult, and the morphological 

 characteristics which were originally em- 

 ployed almost exclusively had given way to 

 chemical and pathogenic tests. Individuals 

 of the same bacterium under different con- 

 ditions will show greater variations than 

 are shown by different species. The fer- 

 mentations produced by bacteria, as distinct 

 from those produced by yeasts, were of con- 

 stantly increasing importance, and had 

 afforded means of splitting up certain com- 

 pounds and isolating new products that 

 could not be obtained in any other way. The 

 compounds fermentable in this way belonged 



to a very few chemical groups, and the 

 products of the change were few in num- 

 ber and comparatively simple in character. 

 It would seem that while the same com- 

 pound might yield different products when 

 acted upon by different organisms, one and 

 the same organism would yield the same 

 products even when it acted on substances of 

 very different composition. By reason of 

 their selective action and their tendency to 

 attack certain compounds in preference to 

 others in the same liquid, bacteria enabled 

 us to separate substances of identical chem- 

 ical composition but different physical proper- 

 ties which could not as yet be separated in 

 any other way. 



Arctic Rivers. The rivers which flow 

 into the Arctic Ocean, said Mr. Henry See- 

 bohm in the British Association, are some of 

 them among the greatest in the world. 

 Some idea of the relative sizes of the drain- 

 age areas of a few of the best-known rivers 

 may be learned from the following, in 

 which the Thames, with a drainage area of 

 6,000 square miles, is the unit : Nine Thames 

 equal one Elbe (54,000) ; two Elbes equal 

 one Pechora (108,000) ; two and a half Pe- 

 choras equal one Danube (270,000); two 

 Danubes equal one Mackenzie (540,000); 

 two Mackenzies equal one Yenisei (1,080,- 

 000) ; two Yeniseis equal one Amazon (2,- 

 160,000). There is nothing that makes a 

 greater impression upon the arctic traveler 

 than the enormous width of the rivers. The 

 Pechora is only a river of the fifth magni- 

 tude, but it is more than a mile wide for 

 several hundred miles of its course. The 

 Yenisei is more than three miles wide for at 

 least a thousand miles and a mile wide for 

 nearly another thousand. Whymper de- 

 scribes the Yukon as varying from one to 

 four miles in width for three or four hun- 

 dred miles of its length. The Mackenzie is 

 described as averaging a mile in width for 

 more than a thousand miles, with occasional 

 expansions for long distances to twice that 

 size. 



Investigation of Earthquake Phenome- 

 na. The committee of the British Associa- 

 tion, appointed to investigate the volcanic 

 and earthquake phenomena of Japan, has 

 reported that the records of horizontal pen- 



