694 



SCIENCE 



[N. S. Vol. XXVII. No. 696 



said that child labor is not an unmixed evil, 

 and that it is chiefly a sanitary question; and 

 by Mr. Eobinson, who suggested old age pen- 

 sions as means of avoiding pauperism. 



Walter Hough, 

 General Secretary 



THE GEOLOGICAL SOCIETY OF WASHINGTON 



At the 202d meeting of the society, held 

 at the Cosmos Club, on Wednesday evening, 

 March 11, 1908, under informal communica- 

 tions, Mr. W. H. Emmons presented a for- 

 mula for determining the angle of intersection 

 of a plane with the strike of a vertical section 

 which is drawn oblique to the strike of the 

 plane. 



Regular Program 

 Preliminary Notes on Recent Earth Move- 

 ments at Butte, Montana, as shown by 

 Precise Levels of the U. S. Geological 

 Survey: E. H. Chapman. 

 In 1904 precise levels were run at Butte, 

 Montana, and many bench marks established 

 with the purpose that they should be used as 

 a base to compare future changes of surface 

 level. 



In 1906 the Coast and Geodetic Survey 

 brought one of its precise lines into Butte and 

 obtained checks on several benches of the 

 1904 work. These checks show ehaiTjes which 

 are interesting. Using a bench mark near the 

 Butte Eeduction Works as a datum and ex- 

 tending the comparison of benches northward 

 an increasing difference is found. 



Difference 



Butte Reduction Works 0.000 



Webster School — .017 



Colorado Street School — .051 



Owsley Block — .436 



Court House — .737 



Government Building — .888 



From the Government Building a compari- 

 son along another line to the flat southward 

 shows a decreasing difference. 



Difference 



Government Building — .888 



Florence Hotel — .791 



Braund House — .130 



South Butte — .051 



Butte Eeduction Works again the zero. 



The maximum change at the Government 

 Building represents a sinking of .444 foot 

 per annum. 



The Owsley Block compared with the Butte 

 Eeduction Works shows a sinking of .344 foot 

 between 1899 and 1904, and of .436 foot be- 

 tween 1904 and 1906, the former giving a rate 

 of .069 and the latter of .218 foot per annum. 

 The figures obtained from the earlier work 

 are not so reliable as those depending upon 

 the notes of 1904 and 1906, but comparison 

 shows the rate of change to be increasing. 



The bench marks were located in the hope 

 that eventually it would be possible to deter- 

 mine if there is continued movement along 

 the local fault planes, but the 1906 work did 

 not include a sufficient number of checks to 

 be of value for this purpose. 



No reliable comparison has yet been had 

 with the benches established on the east side 

 of the continental fault of the Eocky Moun- 

 tains. 



The systematic repetition of check levels at 

 intervals of two years — to bring out the facts 

 of value — was strongly urged. 

 Pleistocene Phenomena of Central Massa- 

 chusetts: Wm. C. Alden. 



The Worcester County plateau is well gla- 

 ciated, retaining in but few places residuum 

 of preglacial weathering. There is much 

 drift in the valleys, but on slopes and crests 

 it is very thin, probably not averaging 15 feet 

 over the area. 



No undoubted evidence of pre-Wisconsin 

 glaciation was observed. Drumlins are nu- 

 merous, while in places the bed-rock surface 

 between them is but thinly covered. Consid- 

 eration of the elevation of the glaciated sum- 

 mits of Mounts Wachusett and Monadnock, 

 their distances from the terminal moraine, 

 and other factors leads to the inference that 

 there may have been 1,500 to 1,900 feet of ice 

 over the central part of the area, and 2,000 

 to 3,000 feet in the Connecticut Valley. 



No moraines of recession are traceable con- 

 tinuously across the area. Terminal moraines, 

 kame and outwash terraces, eskers and delta 

 plains and deposits formed in temporary gla- 

 cial lakes are numerous, but while they enable 



