49- Values of 0.6745^ 



50. " " .6745 V /, 7( ^ 37 



51- " " 



52. " 0.8453 , - ....... .....,,..... 37 



n i 



53. " " the logarithm of the gamma function T(n) for values of n 



between i and 2 3& 



54. " " the first seven zonal harmonics from = o to # = 90 . . . 40 



55. " " log M/4TrVaa l for facilitating the calculation of the mutual 



inductance between two coaxial circles 4 2 



for different values of 6 with the loga- 



|V(i sin^sinV)** 



rithms of these integrals ............ 43 



57. Cross section and weight of copper, iron, and brass wire of different 



diameters, British units ................ 44 



58. Cross section and weight of copper, iron, and brass wire of different 



diameters, metric units ................ 4$ 



59. Cross section and weight in various units of aluminium wires of differ- 



ent diameters ............ ....... 48 



60. Cross section and weight in various units of platinum wires of different 



diameters ..................... 5 



61. Cross section and weight in various units of gold wires of different 



diameters ..................... 52 



62. Cross section and weight in various units of silver wires of different 



diameters ..................... 54 



63. Weight, in grammes per square metre, of sheet metal ...... 56 



64. " " various British units, of sheet metal ......... 57 



65. Size, weight, and electrical constants of copper wire according to Brown 



and Sharp's gauge and British measure ........... 58 



66. Same data as 65, but in metric measure ........... 60 



67. " " " " but British standard wire gauge ........ 62 



68. " " " 67, but in metric measure ........... 64 



69. " " " 65, but Birmingham wire gauge ......... 66 



70. " " " 69, but in metric measure ........... 68 



71. Strength of materials : 



(a) Metals and alloys ................. 70 



() Stones and bricks ................. 70 



(c) Timber ........ ' ............ 70 



72. Composition and physical properties of steel ...... .... 71 



73. Effect of the reduction of section produced by rolling on> the strength of 



bar iron ..................... 72 



74. Effect of diameter on the strength of bar iron ......... 72 



