128 POPULAR SCIENCE MONTHLY. 



duct it tlian any other of the four views. It is creditable to the reason of 

 the persons of other occupations consulted that this group is largest in each 

 class. The hill which is now awaiting the attention of Congress is meddle- 

 some and impracticable. As shown by Dr. Charles W. Dabney, Jr., As- 

 sistant Secretary of Agriculture, in a letter to Senator McMillan, it would 

 seriously hamper the researches of the United States Bureau of Animal 

 Industry, and it has been condemned, among other societies, by the Ameri- 

 can Medical Association, the Association of Military Surgeons of the 

 United States, the National Academy of Sciences (which was founded to 

 advise the Government on scientific matters), the Association of American 

 Medical Colleges, the Association of American Physicians, the Medical 

 Society of the District of Columbia, the Joint Commission of the Scientific 

 Societies of Washington (and several of these societies separately), and the 

 American Academy of Medicine. The greatest mischief of such a law is 

 that it would be used as a precedent for similar laws in the several States, 

 and, what the vivisection prohibitionists incautiously avow, as an " enter- 

 ing wedge " to bring in more drastic measures. America is in a fair way 

 to make vivisection literature of its own. 



Our present knowledge of the ice age afFords an admirable example of 

 reconstructing the past from the present as practiced by geologists. The 

 process by which this reconstruction is effected, the facts relied upon, and 

 the reasoning employed in it are given especial prominence in the recent 

 volume on Ice TFor/c, by Prof. T. G. Bonney* In order to show us what 

 glaciers are and how they act, the author takes us first to the Alps. He 

 points out the lines of debris and the occasional large bowlders carried by 

 the frozen streams, and describes the moraines, giants' kettles, and other 

 traces left by them. Going down the valleys below their present limits, he 

 shows how deposits and marks of erosion testifying to their former greater 

 extent can be identified. Such marks and deposits are found in other 

 lands hundreds of miles from existing ice streams or any mountains that 

 seem adequate to send forth glaciers of great extent. An ice sheet stretch- 

 ing aci'oss a continent must be assumed to account for these phenomena, 

 and Prof. Bonney next shows us the ice fields of Greenland and the 

 antarctic lands as evidence that this assumption is warranted. Leaving 

 existing examples of glacial action, our author draws attention to various 

 traces of the Glacial Epoch lake basins, the parallel roads of Glenroy, eskers, 

 etc. In dealing with phenomena whose meaning is not settled, he has 

 first set forth the facts and then has given the leading rival interpretations 

 of these data, pointing out in what particulars each seems to him strong and 

 in what weak. Traces of ice work are numerous in the British Isles, and 

 nearly one third of the volume is devoted to descriptions of them. In the 

 northeast of England there are the Cromer till, contorted drift, and upper 

 bowlder clays on the Norfolk coast, and similar deposits in Yorkshire, espe- 

 cially in the vicinity of Flamborough Head. In the northwest the Cum- 

 brian Mountains and the adjacent lofty fells of the Pennine range ob- 

 viously have been occupied by glaciers, and the mountainous part of North 

 Wales affords evidence of similar import. The detached mountainous 



Ice Work, Present and Past. By T. G. Bonney. International Scientific Series. Volume 74. 

 Pp. 295, 12mo. New York ; D. Appleton & Co. Price, 31.50. London : Kegan Paul, Trench, Trubner 

 &Co. 



