XX THE translator’s

carry method and perspicuity into every paitof his subject, he takes up the matter ah initio jand in the first: place treats of the resistance offire-arms : in the courie of which, he examinesthe hardness and tenacity of the metals employedin their construction, giving at the same timethe method of refining and fusing them, withremarks on the several proportions in whichthey are to be mixed together. Then, havingmade some observations on the windage, figure,length, and casting of brass guns and mortars, hepoints out the inconveniences arising from whatis called “ the running at the vent,” and con-cludes with the several methods of proving andexamining new guns. The second part of thiswork is entitled " On Projectiles he explainsthe duty of an artillery-oflicer, both on batteryand in the field, as far as regards the initial velo-city of shot, the path of the shot’s flight, andits effects upon works ; and calculates the num-ber of men, that may be killed or wounded inaction, both by round or case-shot fired fromguns of different calibres at various positions ofthe enemy. He draws a comparison betweenthe effects of the howitzers and field pieces,and finishes with a chapter on shells projectedfrom mortars.

The various properties of powder being thus

ascertained,