Reviews. 511 



most commonly in use, which will enable those who have used them the 

 more readily to comprehend the new system. The tal)les published 

 by Hoppus have been greatly improved and extended in this work, and 

 two entirely new tables compiled for it — first, " a table for measuring 

 unhewn, that is round or cylindrical timber, extending in length from a 

 quarter of a foot to fifty feet, and in its quarter girths from one inch to 

 sixty-one inclies ;" and secondly, " a table for measuring hewn or octagonal- 

 sided timber, extending in its lengths from a quarter of a foot to fifty feet, 

 and in width of its sides from one inch to thirty-one inches." 



The Tables are interspersed with valuable hints and explanations, 

 making them clear and, easily understood by the merest tyro. An excellent 

 chapter gives an easy and concise method of measuring and valuing growing 

 timber trees, pollards, and saplings, for which purpose a specimen of a 

 capital form of Field Book is given, and, under the title of " Miscellaneous 

 Remarks," judicious instructions are given on the precautions to be 

 observed in girthing trees ; modes of computing the contents of various 

 shaped solid bodies ; how timber is increased in quantity by additional 

 measurements ; a good form of noting down the dimensions of trees, &c. ; 

 a form of entering trees in the field book according to their respective 

 classes ; a table shewing the number of planks required to make a load or 

 ton of timber ; and a ready method to ascertain the value of timber. 



We recommend the book to the notice of foresters and all who buy or 

 sell timber, who will find it a handy, correct, and valuable companion. 



Tha Colorado Polafo Brelle. By Dr. Ajstdrew Wood, Lecturer on Zoology, 

 &c., in the Edinburgh Medical School. W. and A. K. Johnston, 

 Edinburgh and London. 



A CA.REFULLY got up shilling pamphlet upon this all-absorbing subject, 

 illustrated with the most natural and correctly coloured drawings of this 

 famous insect in all its various stages — from the egg to the full-grown 

 beetle — which has yet been put before the British public. The insects arc 

 shown in their natural size upon the potato plant, and also in a highly 

 magnified state, beautifully and correctly coloured, so that '•' he who runs 

 may read ; " and as the illustrations have been drawn from life with the 

 greatest care, they may be safely relied on as perfect fac-similes, and a trust- 

 worthy guide to the identification of the true Colorado beetle. The letter- 

 press describes, in a terse and lucid style, the history of the beetle from its 

 first discovery, about the year 182Ji, by Messrs. Say and Nuttall in the 

 upper Missouri region, to the present day, when it has become the bugbear 

 of Europe ; clearly explains its life-history, and the causes which favour 

 its spread, and its prodigious powers of reproduction; describing its na- 

 tural enemies, and the best chemical and mechanical remedies against the 

 devouring ravages of the notorious pest ; and in concluding the author 

 makes the following common-sense remark, that " whilst the vitality and 

 powers of increase of the t^olorado beetle are undoubtedly very great, there 

 xists certain natural provisions already detailed, in the shape of bird and in 



