Report of the Hoosac Tunnel and Troy and Greenfield Railroad, by the Joint Standing Committee of 1866. Tappan Wentworth

Adams, a freight house, cashier's office, engineer's office, stable and two coal sheds, and opposite the West End on the Pittsfield and North Adams Railroad, an additional freight house. There are also two instrumental station houses on the east and west summits respectively, all of which are occupied by the State for the purposes of the enterprise. There is also one seven-horse engine and three small compressors. Tho State has also four mule teams, three of four, and one of two animals, making fourteen in all. There were also used on the work in the early part of the year, twelve or fourteen horses, employed in hauling clay, sand, wood, &c. Six of these have been sold to Mr. Farren, and the remainder are to be disposed of. To this enumeration should be added five horses and three or more carriages kept at the stable at North Adams for the transportation of the engineers, superintendent, master mechanic, &c., from point to point along the line of operations wherever their presence and services might be needed.

      for the expense of keeping five horses, and the repairs; which is about five dollars per week in all. The charge for keeping horses at the stable in North Adams, is five dollars per week for feed; and the cost for the use of one horse and wagon from North Adams to the East End, is four dollars. These horses were also used to transport the commissioners and the committee visiting the tunnel, when required for that purpose.

      The Road between the Tunnel and North Adams

      It is proposed to change the course of, the road as it emerges from the tunnel, and two lines have been surveyed, which, diverging near the approach cut, unite again about midway from thence to the village. The difference in length is about thirty feet. The northerly line is the least expensive to construct, and best favors the landholders on the route. It has the recommendation of the engineer, and the approval of the consulting engineer, and will probably be selected. There are reasons for an early location of this portion of the road which call for a prompt action in this behalf on the part of the commissioners, which will undoubtedly be taken.

      The following table shows the expense of the tunnel and the land and works connected therewith under the administration of the commissioners, as found November 1, 1866:—

      The following table shows the cost of the works under the classification of outside and inside expenditures, as given by the consulting engineer.

      The exact correctness of any classification of the expenditures is not very important, inasmuch as the sum total is chargeable to the construction of the tunnel; but the Committee do not see the propriety of charging the engineering and superintendence exclusively to the outside expenditure. They have seen a classification which gave,—

      General Summary of the Force Employed on the Tunnel,

      Experiments

      The interest awakened by the magnitude of the undertaking to tunnel the Hoosac Mountain, and the anxiety manifested for its early completion, prompted the commissioners to the discovery of means to accelerate the progress of the work. Their attention was naturally directed to the operation of drilling, and with a view of improving upon the machine drill used at Mont Cenis; scientific mechanics have been employed to devise and construct a drill that should attain that end.

      As a first step Gouch's patent of the hollow piston-rod, was purchased for New England, for the sum of five hundred dollars. After which, a Mr. Gardner was employed to construct a drill; but his efforts failed of success after an expenditure of thirteen hundred dollars. A Mr. Butler was engaged to devise a machine, but in the course of studying the subject, his health failed and his services were lost.

      A Mr. Hanson completed a machine which promised some success; but on trial it proved a failure.

      A second machine called the Brooks, Burleigh and Gates drill, was made under the direction of the commissioners at Fitchburg. This machine was put upon the works and used for several months.

      A third machine, called the Burleigh drill, an improvement upon the preceding one, was next produced, which is now at the works on the East Heading.

      About $13,000 was spent upon these experiments, resulting in the construction of the Brooks, Burleigh and Gates drill, and the manufacture of four of them. About one-half of this expenditure may be charged to these last drills; the other was unproductive of anything of value.

      The Brooks, Burleigh and Gates drill was patented, but the Commonwealth has the right to use them in the construction of the tunnel.

      These machines will now be described.

      The Hanson Machine

      This machine has a cylinder and valve motion, similar to a steam-engine. The piston is hollow, the drill-bar which may be of any required length, passing through it, is moved with the piston, by means of four wedges or cams on each end of the piston; these cams are pressed on the drill-bar by means of sliding collars forced upon them by a complex arrangement operating alternately. The drill-bar is rotated by means of a ratchet operated by a spiral groove in the shield of the machine. The main difficulty in this machine was in the complex arrangement for forcing the collars upon the cams or wedges. It did not work well in a horizontal position. The machine consisted of one hundred and twenty pieces, and weighed five hundred and ninety-five pounds.

      The Brooks, Burleigh and Gates Machine

      This machine has a hollow piston, the drill-holder being a screw passing through the piston, moving with it, and fed through it, by means of a nut on the end of the piston-rod. This nut is held by means of a cap or union nut, as it is called, the union nut being screwed on to the coupling, and the coupling nut screwed to the piston-rod. The feed-nut protrudes through the union nut, and is allowed to turn round in it. On the end of this feed-nut is a ratchet gear covered by a ratchet-band with an arm upon it, all moving with the piston. The ratchet arm moves up and down in a spiral groove, the groove being in a shield attached by screws to the cylinder; on the ratchet-band there is a pall and two springs, one under the other. One of the springs holds the pall in gear, the other holds it out of gear. As the piston moves down, the outer spring comes in contact with a trip which is on the shield and is lifted up, allowing the under spring to throw the pall into the ratchet, and as the piston is moved back, turns the nut round, thereby feeding the screw forward. At the extremity of its backward stroke, the pall comes in contact with another trip on the shield which lifts it out of gear, the outer spring having a catch upon it which holds the pall when thus lifted out. The rotary motion is given by a ratchet on the coupling-nut, covered by a ratchet-band the arm of which moves in a spiral groove in the shield similar to the other, only having a spring to hold the pall in the ratchet; this rotates all the parts on the piston except the ratchet-bands and cross-head. The latter is held between two check-nuts on the coupling-nut. To this cross-head is attached a bar which communicates with a valve which opens the port when the piston moves back, and shuts it when it moves forward; the air is always on during its backward stroke. The piston having a greater area on the forward than on the backward stroke, overcomes the backward pressure and moves the piston ahead, and when cut off, the continued pressure forces the piston back.