﻿Boolx, Notices. 451 



embrace all artificial salts of inorganic origin. On page 25 it is stated 

 that the Ores of Iron and Manganese are practically the only ores 

 formed by precipitation from aqueous solution, while on page 27 we 

 are told tliat Lead Sulphide and (iold may "under certain conditions" 

 be carried in solution by subterranean waters, and that it is from such 

 waters that they have been deposited in the fissures in which we find 

 them. Again, on page 29 it is stated that veins, " from their mode of 

 formation, are believed to extend indefinitely in depth," while it is 

 generally recognized that they must be confined to a comparatively 

 superficial portion of the earth's crust above the limit of plastic flow, 

 while the statement (page 31) that " depth has no known influence on 

 the character of the vein," is only true of that portion below the 

 limit of surface influences. No Gypsum deposits of any importance 

 occur in the Lower Silurian of the Province of Quebec (page 105), nor 

 are the Clay deposits near St. John, P. Q., " extensively used for the 

 production of porcelain," unless crockery, drain pipes, etc., can be so 

 classed. 



The statement (p. 42) that the Iron Ores of the Archaean (which in 

 the Chart of Ceological Time on page 19 is made to include all pre- 

 Cambrian deposits) are " doubtless metamorphosed bog ores," is rather 

 sweeping, in view of the results of the work of Van Hise and others in 

 the immense deposits of Iron Ore of their age, immediately to the 

 south of Lake Superior. 



That " when a fault is vertical there is no horizontal displacement" 

 (p. 24) also is certainly not true in all cases, while the statement that 

 "the Potsdam Sandstone of Quebec occurs on the south of the Ottawa 

 River in Ontario (p. 168)" has a somewhat Hibernian flavor. 



A number of other little inaccuracies will be noticed in looking over 

 the book, which will undoubtedly be corrected when the second edition 

 is called for, which, judging by the increased attention which is now 

 being directed to our Mineral Resources, will probably be before very 

 long. F. D. A. 



Report of the Geology of a Portion of the Laurentiax 

 Area, lyino North of the Island of Montreal, 



The last Annual Report of the Geological Survey of Canada 

 {Yo\. VIII.) contains a report and map of a portion of the Laurentian 

 area, lying north of Montreal. It is of especial scientific interest, 

 inasmuch as it is the first publication which describes in a complete 

 form all the diff'erent rock structures which are found in a typical area 

 of the Canadian Archaean, with the purpose of ascertaining their true 

 origin. The report is written by Dr. F. D. Adams, of McGill Uni- 

 versity. The first appendix contains a list of the diff'erent publications 

 referring to the Canadian anorthosites, wliile the second is an abridge- 



