...as far as respects the destructibility of the rock, in a greater degree than has hitherto been done. The whole process, therefore, may be summed up under...full effect of the wedge is given in every direction at,the lower part of the charge, but particularly downwards. 3. And, in the last place, to add to the...

...an outline of the process, which may be summed up under the three following heads, viz. 1. To ignite the gunpowder at the bottom of the charge, by means of sulphuric acid, charcoal, and sulphnr. 2. To take advantage of the propelling power of gunpowder, as is done with a cannon ball,...

...an outline of the process, which may be summed up under the three following heads, viz. 1. To ignite the gunpowder at the bottom of the charge, by means...the propelling power of gunpowder, as is done with a cannon ball, only, insteadof a spherical ball, to employ one of a conical form (Jig. 129. a), by which...

...an outline of the process, which may be summed up under the three following heads, viz. 1. To ignite the gunpowder at the bottom of the charge, by means...charcoal, and sulphur. 2. To take advantage of the pro- 129 pelling power of gunpowder, as is done with a cannon ball, only, instead of a spherical ball,...

...of blasting granite rock. The whole process may be summed up under the three following heads ; — to inflame the gunpowder at the bottom of the charge,...by means of sulphuric acid, charcoal, and sulphur; .to take advantage of the propelling power of gunpowder, as is done with a cannon-ball, only reversing...