Evidence of Henry H. Pratt.
“I was foreman at the West Shaft at the Hoosac Tunnel, up to October 15, 1869. In December, 1869, I went to Oil City, Pa., to show Charles Lobb, the contractor for the Jamestown and Franklin Railroad, how to use Nitro-Glycerin for blasting rock. The weather being very cold, warm water was first poured into the holes to prevent the frozen sides of the drilled hole chilling the Nitro-Glycerin. A charge of Nitro-Glycerin was then poured through the water, and a small cartridge of tin being introduced, the charge was fired by means of a frictional electric machine, connected with a priming fuse and a charge of fulminating mercury, being the mode set forth and shewn in the Letters Patent, granted to George M. Mowbray, No. 93,113, and dated July 27th, 1869. I am familiar with the re-issued patents in question, and the mode by which I exploded said Nitro-Glycerin in said tunnel, as above described, is very different from the mode described in the patents re-issued to said U. S. Blasting Oil Company; it would have been utterly impossible to have fired the said three holes in said tunnel by the mode stated in the above referred to re-issues at one and the same moment, as was done by me. I find on examination, that in all the patents granted to Taliaferro P. Shaffner, Nos. 51,671, 51,674, dated December 19th, 1865, the mode of firing a consecutive series of fuses is condemned by said Shaffner, and in patent No. 51,674, that the specification accompanying said Letters Patent contains the following words: “Figures 6 and 7 represent the heretofore known mode of exploding two or more charges by the same electric current, and the former is shewn as applied to a consecutive series of blasts in line, and the latter to the heading of a tunnel,” such mode being identically and exactly what I practised at the Oil City tunnel, and none other. I confirm all the previous evidence as to the feasibility of exploding pure Nitro-Glycerin when unconfined, and also as to the good qualities of the Mowbray Nitro-Glycerin when compared with that made under the Nobel re-issues.”
H. H Pratt.
February 26, 1870.
Evidence of Otto Burstenbinder,
of New York.
“I have been familiar with the use of Nitro-Glycerin since May, 1865, and introduced that article from Hamburgh, Germany, in July, 1865. I witnessed the application of Nitro-Glycerin to blasting purposes about 20 miles from Hamburgh, when many distinguished citizens were present, a full account of the results effected being published afterwards in the principal German newspapers. The mode used to explode Nitro-Glycerin on that occasion was by fuse and cap, the Nitro-Glycerin being confined, in one experiment, in a gas-pipe, plugged at each end, and the fuse led through the plug, and at the end of the fuse there was a percussion cap attached; in another experiment a wooden plug was hollowed out conically inside and the cone was filled with gunpowder; to this plug a fuse was attached and lighted in the usual manner. I myself fired Nitro-Glycerin in the City of New York, on or about the fifteenth day of July, A. D. 1865; this was the first time I used Nitro-Glycerin in the United States, for blasting purposes; the mode of operation was to pour the Nitro-Glycerin into the naked drill hole, and lower a wooden plug charged with gunpowder, on to the Nitro-Glycerin, poured some dry sand on to the plug, and fire a fuse which was situated on the plug in the usual way.
“I am quite familiar with the Nitro-Glycerin manufactured by the United States Blasting Oil Company, under Nobel’s patent, and that manufactured by G. M. Mowbray under his own, and confirm all the previous evidence as to the superiority of Mowbray’s Nitro-Glycerin, in explosive power, in absence of color, absence of smell, absence of nitrous gases, in greater safety through the greater difficulty of exploding it, and in purity. As an expert of considerable experience in the use of Nitro-Glycerin, I assert that it is entirely unnecessary to confine Nitro-Glycerin in order to explode the same, the explosion being as thorough, and its effects nearly as powerful for blasting purposes, owing to the extreme instantaneous conversion into gas when unconfined, provided a proper charge of fulminate be used.
“I have made the explosion of Nitro-Glycerin, and its application to blasting purposes, my occupation since 1865, and am thoroughly familiar with its properties, use, and the literature referring to it, and I have never heard or read that the Nitro-Glycerin made by Sobrero was incapable of being crystallized, but I verily believe, and have always found, that Nitro-Glycerin congeals when exposed to a moderately low temperature.”
Otto Burstenbinder.
June 7, 1870.