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XXXI. Reviews, and Notices respecting New Books. 



A Practical Treatise on Locomotive Engines upon Railways; with 

 Practical Tables, giving at once the Results of the Formula ^ 

 founded upon a great viamj new experiments, Sfc. By the Chev. 

 F. M. G. De Pambour. 



IT is only within thelastfewyearsthatthe attention of engineers has 

 been particularly directed to the mechanical capabilities of loco- 

 motive engines; and their inquiries have, for the most part, been 

 limited to the vague practical information that is commonly inferred 

 from actual experiments. The vast and splendid projects that now 

 occupy such an important position in the public mind, and that pro- 

 mise such extensive and permanent advantages to society, have 

 created a stronger and more lively interest in the science of railways. 

 An engineer is expected to be, at least, practically acquainted with 

 the theory of locomotive engines; he is supposed to possess that in- 

 timacy vvith the laws of their physical and mechanical action, as to 

 be prepared to estimate pretty nearly, on scientific principles, the 

 speed with which any proposed engine will draw a given load. How- 

 far this has really been the case is a question on which it will not here 

 be necessary to offer an opinion ; but we may state, that in the first 

 stages of this, as well as of almost every useful branch of science, 

 the practitioner is obliged at first to glean his information from expe- 

 rience alone. The construction of each successive engine suggests new 

 and valuable information as to defects that may in future be avoided 

 and improvements that may be adopted. The working of each 

 eno-ine also furnishes the means of roughly estimating what may 

 be done by any other of a similar construction. Afterwards, how- 

 ever, when the subject becomes to be scientifically discussed, me- 

 thods are presented by which the capabilities of any intended engine 

 may be previously submitted to an accurate calculation, whatever 

 may be the plan of its construction. We do not think that this 

 object has yet been fully accomplished. The author of the present 

 work, however, treats the subject in a manner that shows him to 

 be well acquainted with the mechanical theory. He first gives a 

 very intelligible description of the locomotive engines employed 

 on the Liverpool and Manchester railway, as well as an account 

 of their dimensions and proportions. He founds the calculations 

 throughout the volume, on a great number of experiments that 

 he has made himself vvith these engines. In the second chapter 

 he gives rather a tedious discussion relating to the calculations of the 

 true pressure of the steam from the indications of the lever and valve 

 of the boiler : this might be abridged with advantage. The fourth 

 and fifth chapters, which treat on the resistance along the railway and 

 the proportions and effects, form the principal feature of the volume, 

 and thev contain a remarkably clear and comprehensive discussion 

 of these 'most important points. The author very properly considers 

 the friction of the engine separately from that of the load, and shows 

 that in conscijueuce of the additional strain on the machinery, it in- 



