Turner's Falls?

With the requisite railroad facilities supplied, it is certain that the growth of a region so abounding in the most essential reliance of mechanical industry, as Northwestern Massachusetts, cannot be measured by the snail's pace which marks the progress of an agricultural district. The farmer's interests are indeed equally promoted with those of other industrial classes, by the opening of railroads, but these do not increase the number of farms or farmers within our borders, nor stimulate the growth of agricultural towns. It is mainly by her manufactures and commerce that Massachusetts has become so prosperous and wealthy. It is because the commercial and industrial interests of the whole State require it, that another route to the West has become a necessity; and it is because such immense resources yet remain to be developed, and such a gigantic power to be employed, in Northern Massachusetts that the new route must pierce the Hoosac Mountain, if it is possible and practicable.

That it is possible to tunnel the Hoosac Mountain cannot be doubted by any sane person who has inspected the half mile already excavated. All of the eminent engineers, whose reports upon the enterprise have been published, say it can be done; nor do any of its opponents pretend to question its practicability. But in order to estimate properly the magnitude of the work, its possible and probable cost, and the time within which it can be done, it is necessary to know what has been accomplished in this department of civil engineering. Fortunately, this needed information is contained in Mr. Charles W. Storrow's very able report on European tunnels. Mr. Storrow is a distinguished civil engineer, who made a journey to Europe in the summer of 1862, by request of the Hoosac Tunnel Commissioners, and with the approval of the Governor and Council, for the purpose of examining the most important tunnels there constructed, and, especially, the one in progress under the Alps. He describes twenty-two tunnels which he visited, besides that of Mt. Cenis. Fourteen of these are in England, seven in France, and one in Switzerland. Two of them are upwards of three miles long, and many of them between one and two miles. Some of the shafts were nearly as deep as the central shaft of the Hoosac. Some of these excavations were made without the aid of shafts, others wholly by means of shafts, without working from the ends at all.

It might be supposed that in the construction of so many subterranean ways, in such different sections of the continent, almost every conceivable geological formation must have been traversed; and so it appears from Mr. Storrow's report. Granite, quartz, oolite, limestone, shale, slate, sandstone, gravel, sand, clay and marl, were the material through which with pick and spade, drill and shovel, the patient workmen made their way. Not unfrequently, more than half the varieties of rock and earth we have named were met with in the same tunnel. Sometimes the work would be interrupted and temporarily abandoned in consequence of an inundation of water, sometimes enormous masses of gravel and sand would work through into a shaft or tunnel, with disastrous and, in two instances, with fatal consequences. In many instances, work was discontinued for years, for want of funds, and then afterward renewed, with eventual success. In fact, about the average amount of those ordinary and inevitable obstacles which stand in the way of all great enterprises, were encountered by the engineers and contractors, in the building of these tunnels; but time, money, and skill, never failed to remove every difficulty. But we propose to extract, and condense from Mr. Storrow's report, a few of the main facts about some of the most important of these works; as the report has, not been read, or even seen by one in a hundred.

The "Box Tunnel" between Chippenham and Bath is more than a mile and three quarters in length. Nearly one half its length passes through a kind of limestone rock, and the other through clay, the clay end being lined with masonry. Five shafts were sunk, the deepest being about three hundred feet. "During the construction of this tunnel, great difficulties were encountered from the excessive quantity of water which inundated the works, sometimes even occasioning their partial suspension, and powerful means were required to overcome the obstacles. At one time the water fairly got the mastery over the machinery used for its removal, and it was only after an additional set of pumps worked by a fifty horse power engine, that the work could be resumed." This tunnel was built in five years, and its cost was about $1,750,000, or about $547 a yard.

The Woodhead Tunnel, on the Manchester and Lincolnshire Railway, is upwards of three miles long. It was originally built for a single track, its dimensions being 14 feet wide at the head of the rails, and 18 feet 3 in. high from the rails to the under side of the arch; which are almost exactly the dimensions of the present section of the Hoosac Tunnel. After a few years of use, the increase of business required another track and so a second tunnel of exactly the same size was built parallel with the first. It is a double tunnel with a thick dividing wall between, pierced with twenty-one arched openings. Five of the original shafts have been kept open. The deepest of these is more than six hundred feet, and the least about three hundred. The rock through which the tunnel passes consists of millstone grit, a hard material, and shale, a kind of indurated clay.

The Kilsby Tunnel is more than a mile and a quarter long, and is built in Roman or metallic cement, under a bed of quicksand, from which it took nine months to pump the water, through shafts on either side of the sand bed. During a considerable portion of that time, the water pumped out was two thousand gallons a minute. The quicksand extended over 1350 feet of the length of the tunnel.

The Watford Tunnel is a mile and one tenth long, excavated entirely from chalk and loose gravel, the treacherous nature of which rendered it a work of great difficulty, streams of gravel and sand sometimes pouring through the fissures of chalk, like water.

The Netherton Tunnel is one mile and three quarters long. For its construction 17 shafts were sunk, their total depth being 3,083 feet, the least depth of any one being 63 feet, and the greatest, 344 feet. There were 36 faces to work at, and the progress at each face was 10 1-2 feet per month. The tunnel was completed in two years.

From these brief descriptions of a few of the tunnels in England examined by Mr. Storrow, one can form a pretty correct opinion of the ordinary difficulties in tunneling which have been met and overcome by the English engineers. Mr. Storrow says that tunnels are not considered there such formidable works as they have generally been esteemed in our Northern States. They are so common that they have long ceased to attract the attention of travelers, more than eighty miles in aggregate length being already in use. Mr. Storrow estimates the average progress made in the construction of the English tunnels at about thirty feet per month on one face, and that the cost per yard varies from $125 to $250, for ordinary tunnels; but where peculiar difficulties were met, the cost has reached to from $500 to $750 per yard.

The Hauenstein Tunnel in Switzerland, one mile and an eighth in length, was from four to five years in being constructed. Two shafts were sunk, one 417 feet, and the other 558 feet deep. Portions of the shafts and tunnel were lined with masonry on account of the water and sand, and varying firmness of the strata passed through, all of which caused many difficulties and delays. The progress made between the intervals of obstruction, varied from fifty-six to one hundred and nine feet per month on a