312 Mr. Mallet on the Plujslcal Conditions 



320. If universal civil engineering experience has, after the most careful in- 

 quiry abandoned the use of cast-iron wherever impulsive and tensile forces are 

 together concerned in structures or machines, and substituted wrought-iron, it 

 is difficult to discover any reason why the same should not be done in the 

 construction of artillery ; which is in itself essentially a work of civil or mecha- 

 nical engineering ; admittedly so, according to some of the ablest military 

 authors. " De este modo la Artilleria es sencillamente una aplicacion imme- 

 diata de la mechauica, contraida al estudio de una especie particular de maqui- 

 nas" (Senderos, Elem. de Artil.) 



The advocacy of this, the attempt to facilitate and perfect it, have been, 

 in part, the aim of what precedes. 



In the attempt, whether successful or not, the author can truly say, in the 

 words of Bacon, that he has endeavoured to lay his mind unbiassed to the 

 question, " so that, like a pui-e mirror, it should reflect natui-e without distortion." 

 He had no preconceived views : and as all the main inquiry of the work had 

 been completed long before he became acquainted with the somewhat meagre 

 literature of the subject abroad, — there is none, he regrets to say, at home, 

 (Note EE), — and wholly independently : so he neither copied the notions, nor 

 was prejudiced by the preconceived views, of others. 



