252 



SCWN'CE. 



[Vol. IX., No. 214 



and in their stead the prairie states are rapidly 

 developing. 



We point out only a few of the important re- 

 sults Siipan obtained by the geographical arrange- 

 ment of statistical data and of his critical remarks 

 on the available material. In studying the indus- 

 try and agriculture of the United States, he again 

 divides them into four groups, — the north-eastern 

 industrial district, the southern and central agri- 

 cultural district, the mining district of the western 

 plateaus, and the Pacific district, in which agri- 

 culture pi'evails while mining and industry are of 

 considerable importance. The character of the 

 United States is still that of an agricultural coun- 

 try, but industry is growing rapidly upon agricul- 

 ture. As compared to these, mining is insignifi- 

 cant, the whole mineral production being only 

 eighteen per cent of the agricultural. As we ap- 

 proach the southern states, the industry decreases, 

 while agriculture increases. Going west, indus- 

 try decreases, and is a minimum in the prairie 

 states ; farther west its importance is again in- 

 creasing. The north-eastern states have changed 

 their character from that of agricultural states to 

 industrial ones. The industry of the United States 

 is founded upon the produce of agriculture, and 

 every province works up its native material, — the 

 southern states, cotton ; the southern-central states, 

 tobacco, iron, etc. The New England states form 

 the only exception. Cotton, wool, and leather 

 manufacture are the predominating industries, — 

 though cotton does not grow there, — and stock- 

 raising is of no importance. The industry of this 

 region has the same character as that of England. 

 It consumes for manufacture the produce of for- 

 eign countries. A map accompanyiug the report 

 illustrates the distribution of industrial production 

 in North America. 



The data on the commerce of the United States 

 do not refer to 1880, as those on production do, but 

 are the mean of the five years 1880-84. Supan 

 prefers this method on account of the irregular 

 fluctviations, which are of greater importance in 

 commerce than in production. lie arranges the 

 commerce of the seaports so as to show that those 

 of the northern Atlantic coast are importing 

 while the southern ones are exporting. In the in- 

 terior the lake district as far as Cleveland is im- 

 porting ; farther west it is exporting. On the 

 Pacific coast the northern ports are exporting, the 

 southern ones are importing, while in San Fran- 

 cisco both branches are of equal value. The ex- 

 port of manufactures is steadily increasing in value 

 as compared to that of agricultural produce. 



The statistical data on Canada show that the 

 proportion of the industrial and agricultural pop- 

 -ulation is about the same as in the United States. 



The principal difference is, that the proportion 

 is evenly distributed in all parts of Canada, 

 while very wide differences exist throughout the 

 United States. Canada is now in a stage the 

 United States passed through before the rapid de- 

 velopment of the western states and territories. 

 The western provinces of Canada are not yet as 

 far developed as those of the United States, and 

 the shifting of production to the prairies, which 

 has been going on here for more than thirty years, 

 has scarcely begun there. 



The present volume shows that results of emi- 

 nent practical value may be obtained by the ap- 

 plication of geographical methods to sociological 

 problems. It opens new points of view to the 

 student of political economy, showing the close 

 connection between man and the country he in- 

 habits. F. Boas. 



Starting from the common observation that 

 when we do hard thinking we cannot at the same 

 time use our muscles actively. Dr. J. Loeb (Pflu- 

 ger's ArcMvf. Fhysiologie) has attempted to esti- 

 mate quantitatively the relation between physical 

 and psychical activity. His method was to record 

 his maximum grip on a dynamometer ; then, af- 

 ter a short rest, to begin some mental work ; and, 

 while engaged in this, to record the maximum 

 grip once more. The result was, that the latter 

 grip was decidedly less powerful, and that the dif- 

 ference between it and the former grip was the 

 greater, the more difficult and absorbing the men- 

 tal process. For instance : in one case the normal 

 grip with the left hand depressed the lever of the 

 dynamometer to 77° ; while reading and under- 

 standing (i.e., he could repeat the substance of it 

 in his own words) a scientific work, only to 15° ; 

 while simply reading it as so many sounds, 67". 

 Another gentleman (Professor Zuntz) could nor- 

 mally depress the lever to 69° ; but, while reading 

 a catalogue of names (requiring little mental strain), 

 to 58°. Dr. Loeb's average maximum grip when 

 not occupied with mental work was (mean of both 

 hands) a depression of the lever to 85'^ ; while mul- 

 tiplying one number under 10 by another such 

 number, the depression was 81*^ ; when the two 

 numbers were between 10 and 20, only 35° ; when 

 between 20 and 30, only 14°. This shows very 

 clearly how the energy given over to the mental 

 exertion is taken off from the muscular effort. 

 It must, of course, be understood that these re- 

 sults have only a general value. The method pre- 

 sents many mechanical difficulties ; the question 

 of attention is an important factor ; and Dr. 

 Loeb simply offers these results as a preliminary 

 statement of his intention to work upon this 

 problem. 



