A crowd of ladies were watching with great attention the Sewing-machinesewing away with the greatest exactness, and much stronger than by the ordinary mode with a needle, as each stitch is a knot. The inventor
here both were preserved. The fowls are of the long-legged Spanish breed, coming to table like trussed ostriches; the plump English barndoor sort are about being introduced. I had nearly forgotten a beautiful and extraordinary inventiona rifle, not heavier than the common one, that will discharge twenty-four balls in succession without reloading. Where the ramrod is usually placed, is a smaller barrel, containing, when filled, twenty-four ball-cartridges, and, after discharging, the action of recocking introduces another cartridge, and so on, until the whole are discharged; the whole twenty-four can be discharged in as many seconds!
After leaving this interesting exhibition, where I could have lingered a whole day, I was joined by a friend, an Americana gentleman of great attainments in scienceto whose remarks I am indebted for the following scraps. The Merrimac, when lowas when I saw itis a trifling stream, having a bottom of laminated rock, worn in channels by the stream. At spring and fall, there is ten or fifteen feet of depth; and to remedy this inequality, an important work was undertaken and executed: to this we bent our way. It is a canal in form, but should more properly be called a reservoir. It is 1¼ miles long, 100 feet wide, and 15 feet deep; of solid granite, sides and bottomequal in durability to any work, ancient or modern. It is about half way cut through the solid granite rock, which in that part furnishes a natural wall. My friend had watched its progress, and gave me many interesting details of the engineering processes employed: among others, the tremendous application of steam and gunpowder. An engine bored holes in the rock fifteen feet deep and twelve inches in diameter; and these were so placed, and in such numbers, that at a single blast 170 tons of granite were blown into the airan operation hardly conceivable. This canal leaves the town in a westerly directionbeing, at its outset, about a quarter of a mile from the Merrimac, but gradually approximating for a quarter of a mile, until it touches and unites with that river. Between the two, is one of the prettiest of public walks, ten feet wide, having rows of trees on each side, and terminating in a point; being the end of a splendid granite wall, at its base thirty feet thick, and tapering to half the thickness, dividing the natural from the artificial stream. Here we come to a point of great interest: on the right is an artificial dam across the river, with two sharp lines at an angle of sixty-seven degrees, the point meeting the stream, thus stopping the waters, and insuring a supply for the reservoir, while it forms a cascade of about twenty feet.
My friend gave me a very graphic description of the opening of the works. The whole was built in a cofferdam, quite dry, and the opening was a holiday. Every spot within sight was covered with spectators, for whom the engineer had contrived a surprise. The works used in keeping the water out of the reservoir, and protecting the new dam, were undermined, and charged with gunpowder. At a given signal, the train was fired, and in an instant the whole blew up; and when the smoke cleared away, the fragments were floating down the Merrimac, and the canal full of water.
On the left from the point, the egress of water is regulated by flood-gates of a superior construction. The building crosses the canal, and contains seven huge gates, which are raised or dropped into their places by beautiful machinery. To each gate is attached an immense screw, which stands perpendicularly, twenty feet long and ten inches in diameter. At its upper end, it passes through a matrix-worm in the centre of a large cog-wheel, lying horizontally The whole is set in motion by the slightest turning of a handle; and here I saw the application of the Turpin Wheel I spoke of beforeno engine or complication, but a wheel fifteen feet in diameter, fixed horizontally, submerged in the stream, receiving the falling waters, and thus rapidly revolving, and by a gear, giving motion to the machinery for raising or lowering the immense gates, stopped or set going by merely turning a stop-cock, and requiring no more force than an ordinary water-cistern.
I cannot leave this interesting spot without an attempt to describe the beautiful scene. A little to the right, the river widens into a sort of bay, with several fine islands covered with wood; in front, across the stream, as far as the eye can reach, are the forests of New Hampshire, with occasional headlands of greensward. In the autumn, it has exactly the appearance of a gigantic flower-gardenthe trees being of every imaginable colour. 'Ah!' said my friend, 'this is an interesting spot: it was the favourite residence and hunting-ground of the Chippewas. The Indians,
like your monks of old in Europe, always chose the most beautiful and picturesque sites for their dwellings; but they have retired before the advance of a civilisation they could not share or appreciate.' Talking in this way, as we returned, he called my attention to a singular phenomenon in the river. At some remote period there was, and it remains to the present moment, a rock standing in the middle of the stream, about twelve feet in diameter at the top, of an irregular form, and of the hardest granite. By the action of the water, a mass of granite had been thrown on the top, where it lodged. At high-water, perhaps during three months in each year, the stream had caused this mass to revolve on its own axis, until it has worn itself of a round figure, and worn also the rock into a cup, now about six feet deep. Still, it revolves when the water reaches itnature still plays at this cup-and-ballthe ball weighing five tons. Talk of this sort brought us to the railway. In due time I reached home; and I do not remember to have ever been more interested than by the day spent at Lowell.