involved in the Construction of Artillery. 427 



SECTIONS. ^ _ PAGE. 



70 The author's general classification of the principal makes of British cast-iron as 



applicable to artillery; Table III. 171,172 



CHAPTEE VIII Causes of Liability to Borsting in Firing Red-hot Shot. 



7 1 Causes heretofore assigned ; wedging by expansion in the gun, &c., 1 73 



72 Expansion at red-heat of cast-iron shot, 173 



73, 74 Effect on expansion of casting in iron moulds or in sand; permanent enlargement 



by heating, 173 



75,76 Disproof of the common theory ; Tables of expansion and windage, 174 



CHAPTER IX Nature and Effects of Local Expansion by Heat on Guns. 



77 True cause stated; strain upon the exterior produced by expansion of the interior 



of the chase, 1 75 



78-82 Conditions of heating internally and cooling externally, explained, . . . 175,177 

 83-85 Actual Telocity of transmission of the heat through the metal of the gun ; want of 



data; Biot's formula and experiments, 177, 178 



86, 87 M. Weidmann's researches; sufficient proofs ofgreat disproportion between tempe- 

 rature of the interior and exterior of the gun, 1 79 



CHAPTER X Mechanical Equivalent of Expansion by Heat. 



88 General formula for mechanical equivalent of heat, in dilatation or contraction; 



assumes the body absolutely hard, and its elasticity perfect, and not true in 

 nature, 180 



89 Equations for such strains applied to guns; limit, when equal to the repairing 



strain, 181 



CHAPTER XI Numerical Example. 



90 64-pounder firing red-hot shot, 181 



91 Relations of the tangential and longitudinal strains ; general equations, .... 182 



CHAPTER XII. — Effect op a Heated Gun on the Chaiige. 



92 Ignition and explosion of the powder more rapid in the heated gun, 183 



CHAPTER XIII. — Phenomena induced in quick Firing; Limit of Heating. 



93 Effects of strain on the gun analogous to those of firing hot shot, 183 



94 Theoretic limit of the quantity of heat communicable from one discharge; general 



expressions for cast-iron and gun-metal, in terms of the weight of the gun and 



of the charge ; example, 183 



CHAPTER XIV Explanation of Drooping at the Muzzle. 



95 Drooping at the muzzle a case only of relatively greater expansion of the top side 



of the gun; the common notion of its cause impossible, 184 



96 Illustration and reference to Plate IV., 185 



97 Flexure when the gun is supported at both ends horizontally, and only by the 



trunnions 185 



