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XXIV. Notices respecting New Books. 



Diary of a Magnetic S / a Portion of the Dominion of Canada, 



chiefly in the North-western Territori tutcd in the years 



1842-44. Bo Lieutenant Lefbot. E.A.* now General Sir J. H. 

 Lepeot, CJR, K.C.M.G.. F.Z.S.. fa 



T^HE late Sir J. Hersehel. in an article on " Terrestrial Magne- 

 -■*- tism." which appeared in the ' Quarterly Review." June 1840, 

 strongly advocated the carrying out of Magnetic Surreys of the 

 Colonies. The late Gen. Sir E. Sabine, then Major E.E., in 

 Xovember 1840 addressed a letter to Sir J. Hersehel, as Chairman 

 of the Committee of Physics of the Eoyal Society, referring to the 

 'Quarterly Eeview * article, aud containing proposals for a Mag- 

 netic Survey of the British Possessions in Xorth America. The 

 Committee laid this, and other letters on the subject, before the 

 Council, with a strong recommendation that Government should be 

 urged to have the proposed Survey executed. The Eords of the 

 Treasury acceded to the proposal, and on July 20. 1542, Lieutenant, 

 now General. Sir J. H. Lefroy. left England to take charge of 

 the Observatory at Toronto, with the duty of carrying out the 

 Magnetic Survey annexed. 



This duty was completed by the close of 1S44, and the general 

 results only having been embodied in Sabine's memoir " Contri- 

 butions to Terrestrial Magnetism " (Xos. 7 and 11. Phil. Trans. 1S46, 

 1^72). Sir J. H. Lefroy has been led by the renewed attention 

 directed to the Distribution and Periodical Changes of the Earth's 

 Magnetism, to present the observations of his Survey with fuller 

 explanation and in a form more convenient for reference. 



A Preface of pp. xxii gives the correspondence, out of which the 

 Survey originated, as well as other particulars : concluding with some 

 remarks on the subject of local anomalies in Magnetic Elements, 

 reference being made, among other publications, to the recent 

 Eeport of the U.S. Coast Survey for 1881, 



Part L. pp. 5^, is devoted to an account of the Instruments 

 employed, and a general description of the observations made with 

 them, followed by a discussion of the probable errors involved and 

 other connected matters. To this succeeds the Diary of * ; a 

 journey which was specially laid out for scientific work and almost 

 excluded sport or excitement of any kind." containing the records 

 of observations made from day to day between May 1843 and 

 November 1^44. starting from Montreal the observers' route was 

 up the Ottawa and down the Ereneh Eiver to Lake Huron, along 

 the X. shore of Lake Superior to Port William, by way of Lake of 

 the AVoods. Lake ^Winnipeg, and Hill Eiver to York Eaetory on 

 Hudson's Bay, thence by Lake Athabasca to Eort Chipewyan 

 (September 23 j, where the author "was warmly received by the late 

 Mr. Colin Campbell, and resided with him until March 4, 1844. 

 The arrival created a sensation in the small community, for it was 

 twelve vears *ince anv traveller had arrived by canoe from the 



