The progress during the six months ending May, 1866, was 338 feet; an average per month of 56 feet 4 inches. One week was lost in June in introducing the machine-drills, in consequence of which the progress that month was reduced to 50 feet 6 inches. During the five months ending November 30, the progress has been 219-1/2 feet; being an average of 43.9 feet per month. It will be seen by the table, that in July, the first month after the introduction of the drill machines, the progress attained was only 26.5 feet. As the men became better acquainted with them, the progress was increased to 48 feet in August, and in September it rose to 54.5, having nearly attained the average progress of the six months preceding their introduction. Had there been an adequate supply, there can be little doubt that the progress would have continued to increase, and would have shown the superiority of the machine-drill over hand-labor; but the supply fell off, and the progress in October was reduced to 34 feet and 6 inches.

_Table showing the progress at East End Heading, from November 1, 1865, to January 1, 1867._

===========================================

Distance from

Progress.

DATE.

Portal.

----------------+---------------+---------- Nov. 1, 1865,

2,839.0

Dec. 1, 1865,

2,904.0

65.0 Jan. 1, 1866,

2.950.5

46.5 Feb. 1, 1866,

3,005.0

54.5 Mar. 1, 1866,

3,052.0

47.0 April, 1, 1866,

3,115.0

63.0 May 1, 1866,

3,176.5

61.5 June 1, 1866,

3,227.0

50.5 July 1, 1866,

3,253.5

26.5 Aug. 1, 1866,

3,301.5

48.0 Sept. 1, 1866,

3,356.0

54.5 Oct. 1, 1866,

3,394.5

38.5 Nov. 1, 1866,

3,431.0

36.5 Dec. 1, 1866,

3,473.0

42.0 ===========================================

THE CENTRAL SHAFT.

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-cla.s.s 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--

Engine-men and firemen, 5 Mechanics in iron, 4

Carpenters, 5 Blacksmiths and helpers, 4 Pump men, 1 Manual laborers, 39 -- Total in July, 58

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 18-1/2 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._

======================================== DATE.

Distance

Progress.

down.

==================+==========+========== Nov. 1, 1865,

200.8

Dec. 1, 1865,

220.1

19.3 Jan. 1, 1866,

232.5

12.4 Feb. 1, 1866,

250.7

18.2 Mar. 1, 1866,

264.1

13.4 Apr. 1, 1866,

280.9

16.8 May 1, 1866,

297.1

16.2 May 5, 1866,

300.5

3.4 June 1, 1866,[A]

300.5

July 1, 1866,[A]

300.5

Aug. 1, 1866,[A]

300.5

Sept. 1, 1866,

311.9

11.4 Oct. 1, 1866,

331.1

19.2 Nov. 1, 1866,

354.0

22.9 Dec. 1, 1866,

377.0

23.1 ========================================

[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 antic.i.p.ation, 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.

WEST SHAFT.

This shaft has an area of about 8 by 13 feet, and was excavated by Messrs. H. Haupt & Co. Its depth is 316 feet.

The buildings here used by the State are the West Shaft house, the New Shaft building, a blacksmith shop containing two forges, a powder-house, a horse-shed, ash-house and tank-house. The buildings owned by the State and leased to operatives are a boarding-house and four old shanties built by H. Haupt & Co., four first-cla.s.s shanties, eight common shanties, and a double cottage. The buildings at the West End, are connected on the books with those at the West Shaft, and will be here enumerated. They consist of a carpenter's shop, time-keeper's office, a blacksmith shop containing one forge, tool-house, powder-house, horse-shed, brickyard shed, brickyard, engine-house, artesian wells Nos.

3 and 4, buildings, and two-thirds of a barn, which are occupied by the State. One boarding-house, store, one-third of a barn, the Harrington farm-house, barn and out-buildings, twenty-seven common shanties and brickyard boarding shanty. These buildings, with part of blacksmith shop, part of carpenter's shop and time-keeper's office, are rented to operatives and to Mr. Farren, the contractor for constructing the brick arch.

The cost of the structures, as reported in July, at both places, was $35,550 94 As reported in November, 40,010 13

This large increase was mainly occasioned by the construction of a double cottage and necessary buildings at the brickyard and West End.

The amount of rents at these two points is $2,462.60 per annum. Fifteen of the tenements at the West End are leased to Mr. Farren, in accordance with his contract.

The working force at the West Shaft in July was,--

Engine-men and firemen, 4 Carpenters, 2 Blacksmith and helpers, 8 Masons, 2 Truckman, 1 Pump-man, 1 Manual laborers, 105 --- Total, 123

November 1st the working force at this point, including one resident civil engineer, was 103

At this point there is one engine of 100-horse power and one of 40-horse power, and one compressor having four cylinders of a diameter of 13 inches and 24 inches stroke. The West heading from this shaft was advanced 293 feet, and the East heading 1,042, on the first day of December, 1866. The progress for the year ending November 1, 1866, at the heading at this point was 636.7, being a fraction over 53 feet per month. For the last four months, ending December 1, 1866, the progress was 322.1, being a fraction over 64 feet per month, which exceeds by four feet per month the highest estimate for hand-drilling by the engineers in 1862, and by thirty and one-third feet the estimate of Mr.

Latrobe. The progress of the work at this heading during the last six months, making allowance for the influx of water in November, having exceeded the highest estimate for hand-drilling, should be regarded as evidence alike of the skill of the miners and the good management of the engineer and his subordinates.

_Table showing the progress at West Shaft, East Heading, from November 1, 1865, to December 1, 1866._

======================================= DATE. Distance from Progress, shaft, feet. feet.

--------------------------------------- Nov. 1, 1865, 367.5 Dec. 1, 1865, 414.4 46.9 Jan. 1, 1866, 459.4 45.0 Feb. 1, 1866, 503.0 43.6 Mar. 1, 1866, 546.5 43.5 April 1, 1866, 584.8 38.3 May 1, 1866, 623.3 38.5 June 1, 1866, 682.1 58.8 July 1, 1866, 746.1 64.0 Aug. 1, 1866, 810.5 64.4 Sept. 1, 1866, 871.4 60.9 Oct. 1, 1866, 945.4 74.0 Nov. 1, 1866, 1,004.2 58.8 Dec. 1, 1866, 1,042.0 37.8 =======================================

The West heading at this shaft was at first driven 6 feet by 11. It has been found advisable to enlarge it to the dimension of 10 feet 6 inches by 15 feet. This work has been performed by contract. The first letting was at the rate of four dollars per cubic yard, the State furnishing the materials used and removing the stone. The contractors at this rate could not pay their expenses. It was raised to six dollars per yard which was found not to pay, and in July the price was advanced to seven dollars and fifty cents. The State pay the men, charging the same to the contractors, and keep their time. Good progress is made and the work is done to the satisfaction of the engineer.

The East heading at this point was being enlarged also by contract, from 6 feet by 15, to 10-1/2 by 15. The work commenced on the 15th of July, 1866; the price paid is seven dollars per cubic yard; the contractors load their own stone and also that coming from the heading. The State provides the materials used, and hoist the stone to the surface. While the work of the miners at the East heading and of the contractors upon both enlargements was progressing in a very satisfactory mariner, the whole was arrested by an unexpected and somewhat sudden influx of

WATER IN THE TUNNEL.

On the 27th of November the miners working east from the West Shaft struck a seam running across the stratification of the mountain. Water soon issued from the seam at the rate of twenty-three gallons per minute. On the 29th, the water had risen at the foot of the shaft to two and a half feet above grade, and the work was stopped. The usual speed of the engine working the pump was forty-two revolutions per minute; it was increased to fifty-six, and at that rate it succeeded in preventing any further rise of the water. It became necessary to increase the power of the pumps. The plunger was enlarged from eight to ten inches, and a third lift pump was added. To affect this arrangement the pumps were stopped from 9 o'clock, A. M., December 7th, to 3-1/2 P. M. on the 8th.

At this time the water was four feet and eight inches above grade. On the 12th the water was so much reduced that the miners recommenced work.

The next day, at 2 P. M., the water was struck in large quant.i.ties, the whole flow from the heading being 100 gallons per minute. On the 14th, the work was again suspended, and unsuccessful attempts made to stop the water by means of wooden plugs driven into the seam. The pumps working with the longest stroke and at increased speed, were just able to keep the water from rising.

On the 19th, at 10.30 A. M., one of the trunnions of the pump-bob broke, and seriously injured the pump gearing and boxes. On the 21st a new trunnion was put in, and the pump was attached to the small hoisting engine, the water now being seven feet above grade. On the 28th, at noon, the breakages being all repaired, the large engine was again attached to the pumps, the water then being nine feet and eight inches above grade. And, on the first day of January, at 4 P. M., the water stood nine feet ten inches above grade at the foot of the shaft.[B]

[B] At the time of the presentation of this Report, the Committee understood that the water was entirely removed from the shaft and tunnel.

THE NEW SHAFT.

This shaft is located about 264 feet westerly of the West Shaft. Its dimensions are six feet by thirteen in the clear. The rock to be removed from an area of eight feet by fifteen. The labor is done by contract.

The first price was $40 per foot; increased July 1, 1866, to $50 per foot. The State furnishes all the materials for construction, and the power to raise the stone and water from the shaft. The depth of the shaft will be 277 feet when open to grade. On the first day of December, the miners working down had progressed 180 feet, and those working from the tunnel up 45 feet. It was then calculated that the shaft would be excavated in two months. Plans for permanent pumps had been prepared; to furnish the pumps according to the plans, would take several mouths. In the meantime, a temporary pump was to be made at North Adams, under the direction of the engineer.

On the first day of January, about thirty-eight feet of stone remained for excavation in this shaft. The water in the tunnel stopped the work from below, and the work is driven upon one face only at the present time.

There are two small engines at this point, one of fourteen and one of ten horse power. The pumps at this shaft, if constructed agreeably to the design of the engineer, will discharge sixty-five gallons to a stroke and are to be worked by a bull engine. The lift of the water will be eighty feet less than at West Shaft, being discharged about 40 feet below the surface.

THE WEST END.

The work at the West End of the tunnel is under contract. Mr. B. N.