Читать книгу Report of the Hoosac Tunnel and Troy and Greenfield Railroad, by the Joint Standing Committee of 1866 - Tappan Wentworth - Страница 4

There is at this point, used by the State in the prosecution of the work, the shaft-building, a carpenter's shop, a blacksmith's shop, a saw-mill, powder-house, gas-house, ash-house, wood-shed, and a barn; and in connection with the work, a store, a boarding-house, the Thacher farm-house and out-buildings, 4 first-class and 7 common shanties. The cost of buildings at the Central Shaft in July, 1866, was $11,080.13. The cost in November, 1866, was $12,026.83. The annual rent of that portion leased to operatives is $736.

A farm, containing 250 acres of land, with a dwelling-house and barn, has been purchased, adjoining the Central Shaft, for the sum of $3,000. The land was well covered with timber, about one-half of which has been cut for the purposes of the shaft and tunnel. There is estimated to be one million feet of hemlock timber still standing, which will be wanted in the progress of the work. This purchase was an advantageous one for the State, there having been already realized from it an amount equal to its cost.

The working force at the Central Shaft in July, 1860, was comprised of—

On the first day of November there were employed at this point, in all, 81. Of this number, 40 were engaged out of the shaft, and 41 in the shaft.

The above enumeration does not include the resident engineer and time-keeper, stationed here in November.

The depth of Central Shaft, when completed, will be 1,037 feet from the surface; its form is an ellipse, whose axes are 27 and 15 feet. On the fifth day of May it had reached the depth of 300.5 feet. At this time the hoisting apparatus was removed from the shaft, and the work of excavation ceased. The new hoisting apparatus was fitted on the first day of August, and the drilling commenced at midnight on that day.

Previous to the change in the hoisting apparatus, the monthly progress had averaged about 18¹/₂ feet per month. The advance in October and November was 46 feet; the gain over the previous rate of progress is attributable to the practice of simultaneous blasting.

On the first day of January, 1867, the shaft had been sunk 393 feet, leaving for excavation 644 feet.

Table showing the progress at Central Shaft from November 1, 1865, to December 1, 1866.

^[A] Work suspended to put in new hoisting apparatus.

The present hoisting apparatus is expected to be sufficient to finish the shaft. It has two wire ropes, each 1,260 feet long. The time for a round trip is seven minutes. The engine here is of 100 horse-power. The blacksmith shop contains two forges. At the small machine shop the repairs required here are made, as also some repairs for the West Shaft.

The Central Shaft, though designed to aid in ventilating the tunnel, was intended also to accelerate its construction by affording to the process of excavation four faces instead of two during some portion of the work; and the former chairman of the commissioners expected by the aid of machine-drilling, the shaft might be completed in one year from the time such drilling should commence within it. In this anticipation, ten vertical drilling machines were constructed to work in the shaft area and a compressor with two cylinders was provided to furnish the power for operating them. The want of drilling machines at the East End became so urgent, that these vertical ones were changed to horizontals, and used at that point, and the sinking of the shaft by hand-drilling still continues. But if the experiments now in progress at the East End with the new drilling machine shall demonstrate its superiority over hand labor, the machine will doubtless be introduced into the shaft.