Geology and Mineralogy. 335 



next Congress and to take steps to inaugurate the work. A 

 preliminary circular has been issued, giving the plan as thus 

 far developed. The photographs are to be published in quarto 

 form, as separate plates, with one to two views on each ; a leaf 

 of the same form will accompany each plate, giving a brief expla- 

 nation, a chart showing the point of view, etc. It is estimated that 

 some 500 to 600 plates will be needed to print all the types of 

 relief as classified according to the provisional scheme adopted. 

 If, in addition to these, regional series are arranged for, the number 

 may be increased two or three times. The price proposed is one 

 franc for a single plate or half that sum when a series of 100 are 

 subscribed for. Of the various series planned the Committee 

 wishes to go forward first with those dealing with the forms 

 determined by tectonic conditions (faults, folds, etc.) and those 

 connected with glacial action. Photographs relating to these 

 two subjects are solicited and at the same time subscriptions are 

 asked for parts of the work. Communications may be sent to 

 one of the Executive Committee : Prof. J. Brunhes, Fribourg, 

 Switzerland ; Prof. E. Chaix, 25 Avenue du Mail, Geneva ; Prof. 

 Em. de Martonne, 248 Boulevard Raspail, Paris. 



5. The Illinois Oil Fields in 1910 — R. S. Blatchley, of the 

 Illinois Geological Survey, has issued a circular giving an 

 account of the production of oil in the state during 1910. The 

 estimated amount produced for the year is 35,000,000 barrels, 

 while that of 1909 was not quite 31,000,000 barrels. Extensive 

 explorations by drilling have been conducted at numerous points. 



6. Physical JVotes on Meteor Grater, Arizona. — The interest- 

 ing but as yet unsolved problems connected with Meteor Crater 

 in Arizona (see vol. xxx, 427) have been discussed in a paper by 

 W. F. Magie in the Proceedings of the American Philosophical 

 Society (vol. xlix, pp. 41-48). After describing the locality and 

 the general character of the specimens found, he goes on to give 

 the results obtained from some magnetic experiments with a 

 cylinder of the Canyon Diablo iron. Briefly stated, these showed 

 it to have a magnetic permeability about one-half that of a cylin- 

 der of Norway iron. Experiments were also made with the 

 shale balls : one of these, nine inches in diameter and entirely 

 oxidized, was examined as it lay in the pulverized sandstone of 

 the outer rim of the crater. It showed strong local poles over 

 the surface, with, in general, south polarity on top and north at 

 bottom. Another piece of a shale ball, which at the crater 

 showed distinct polarity somewhat irregularly distributed, after 

 arriving at Princeton in a box with other specimens, had lost its 

 polarity and behaved like soft iron. Much of the shale is so 

 feebly magnetic as hardly to affect a needle even close to it. The 

 observations of Baker in 1891 showed no evidence of a local 

 magnetic field within the crater, while the whole variation in the 

 dip of a vertical needle was such as might have been due to 

 errors of observation or perhaps to local conditions, such as the 

 presence of iron pipes in the drill holes. Whether the size of the 



