POPULAR MISCELLANY. 



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be said to have come up to a fair average. 

 The presidential address of Dr. Huggins was 

 a learued and able exposition of the spec- 

 troscopic and photographic investigation of 

 the sky and of the results accruing from it. 

 The addresses of the presidents of sections 

 were mostly historical or special in character, 

 and lacked the abundance of features of living 

 interest that have marked some of the like 

 addresses in past years. In the Section of 

 Physics and Astronomy Prof. Lodge de- 

 scribed his investigations as to the behavior 

 of the ether in the presence of rapidly mov- 

 ing bodies, which, without leading to deter- 

 minate results, indicated that the ether was 

 not affected by them. A noteworthy paper 

 read in this section was that of Prof. H. A. 

 Newton on The Action exercised by the 

 Planets on the Meteorites of our System. 

 In the Chemical Section Prof. Roberts Aus- 

 ten invoked more attention to the metallur- 

 gical branch of the subject, and presented 

 the problems, practical and scientific, with 

 which the metallurgist has to deal. The 

 alloys especially were spoken of as offering 

 a profitable field, and " traces " as possibly 

 having a more important bearing on the 

 properties of the substances in which they 

 are found than has been supposed. The 

 address of Prof. Rupert Jones in the Geo- 

 logical Section related to coal, and showed 

 that further investigation is still desirable 

 in tracing the true origin of the coal-beds, 

 and the ages to which their materials origi- 

 nally belonged. Francis Darwin spoke in 

 the Botanical Section on Growth Curvatures 

 in Plants, and gave the results of his long and 

 minute investigations on the subject. Mr. E. 

 G. Ravenstein presented to the Geographical 

 Section an account of the progress of cartog- 

 raphy and a justification of geographv as 

 a distinct and profitable branch of inquiry. 

 Some of the most interesting papers read at 

 the meeting were presented in this section 

 by women: an account of her journey to 

 Kilima Njaro, by Mrs. French Sheldon, and 

 Mrs. Bishop's (Miss Isabella Bird) account 

 of her observations in the Bakhtiari country. 

 Prof. Cunningham, in the Section of Eco- 

 nomics, stated some problems of high im- 

 portance in that science ; while in the Me- 

 chanical Section Mr. Foster Brown's address 

 dealt mainly with details as to recent me- 

 chanical inventions ; and Prof. Max Miiller, 



in the Section of Anthropology, demonstrated 

 the complexity of the problems of ethnical 

 relationships, and showed that no one class 

 of data, whether of language or physiology, 

 or other, is competent alone for their solu 

 tion. The next meeting of the Association 

 will be held at Edinburgh, with Sir Archi- 

 bald Geikie as president, August 3, 1892. 



Tests of Paper. — Paper lends itself to 

 many frauds which it is of interest to be 

 able to detect ; and it is desirable to know 

 how to measure its principal quality — re- 

 sistance to tearing. The processes for de- 

 termining these conditions are very simple. 

 There are also special details with which few 

 are acquainted. Important differences are 

 noted between machine - made and hand- 

 made paper. In machine-made paper the 

 resistance to tearing and the quality of ex- 

 tensibiUty vary according as the force is 

 exerted lengthwise or crosswise ; the differ- 

 ence is in the proportion of two to five. 

 The resistance is greater in the direction of 

 the length, while extensibility is greater 

 in that of the breadth. The differences are 

 explained by the method of making paper 

 by machinery. The veins of fluid running 

 out from the reservoir extend themselves 

 along the metallic network without any real 

 tendency to associate themselves closely with 

 the neighboring veins, while the current 

 lengthens the fibers and felts them in the 

 direction of the length. In hand-making, 

 the paper is homogeneous, equally resistant 

 in both directions — a demonstration of the 

 superiority of hand-work. There is no draw- 

 ing out and felting in one direction, to the 

 exclusion of the other; but the felting is 

 equally distributed over the whole surface. 

 Jlachine-made papers can not be stretched 

 much in the direction of their length, for 

 the method of fabrication has already 

 stretched them to near the extreme limit of 

 extension. The simplest means of testing 

 the durability of paper as against the usual 

 mechanical agents of destruction is rubbing 

 it between the hands. After such treat- 

 ment poor paper is full of cracks and holes, 

 while strong paper simply takes the appear- 

 ance of leather. The experiment also tells 

 something of the composition of the paper. 

 If much white dust is produced, we know 

 that the paper contains earthy impurities ; 



