From the foundery we proceed, across the open yard, to the smithy, a large, lofty, well proportioned apartment, containing two enormous steam-hammers, the speed and consequent impetus of which can be modulated by a very easy application of manual force, at the pleasure of the operator, so that they can be made either to rise and fall as slowly as the maces of Gog and Magog on the great bell of Saint Dunstan's, or to impinge upon whatever is objected to their descent with a velocity which almost mocks the eye.
In this apartment and its adjunct forge there are no less than eighteen scithies, the bellows of all which are worked by the ubiquitous power of the engine, with anvils of all manners and sizes in due proportion, and sturdy operatives plying them with tranquil and regulated industry, worth five times the amount of human force exerted unequally and impulsively, by fits and starts. These men, for the most part, and, in fact, always when not called off by some casual and unexpected pressure of business in some one department, are kept constantly employed at that peculiar species of work with which each is the most familiar, such method and system in the subdivision of labor being found to insure not only the greatest excellence, but the greatest celerity of workmanship.
In this shop all such portions of the engines, presses, large and small, printing and inking machines, and of the machinery by the agency of which the above machines themselves are created, as are composed of wrought metal, are forged, welded, made new from the commencement, or repaired in ease of damage. For it is worthy of remark that, although many of the labor-saving machines and tools are of English make-not a few by the celebrated Whitworth, said to be the first tool-maker in the world there is not one that cannot, on emergency, be made, mended, or altered, within the precincts of the establishment; while many of the most admirable contrivances are patents and inventions peculiar to this country and this firm.
Immediately adjoining the smithy, is the engine and machine-shop, and on the same floor the large lathe-room containing four enormous surface lathes and two turning lathes, for drilling, boring, turning, . and finishing both circular and horizontal surfaces. From this point, we shall proceed to the saw works, preferring to take each separate department of work by itself from the commencement to the end, rather than to adhere to the precise order and position of the several rooms. as situated in the building.
The first room devoted to this branch of manufacture, which is a very considerable and important item in the business of Messrs. Hoe & Co., the annual sales amounting to not less than 140.000 dollars, in circular-saws, mill-saws, pit-saws, and crosscut- saws, for all parts of the country, is known as the saw-shop. Herein is performed the business of smithing, teething. and blocking the great saws; hundreds of thousands of which are at work, driven by water or by steam-power in every portion of the boundless territories of the United States, to which the enterprising foot and adventurous axe of the white settler has found access-clearing with their restless and indomitable teeth the solid and tenacious fibres of the gnarled live-oaks in the pestilent swamps of Florida, and the dank" regions far away, by Pascagoula's sunnv bay," into the crooked knees of mighty vessels, 'that shall set at naught the howling billows of the wild Atlantic. and the blasts of the mad stormwind, Euroclydon, riving into planks and beams and timbers, that shall build up the places of commerce, and the happy homes of our lordly cities, the white and penetrable flesh of "those captive kings so straight and tall, those lordly pines, which fell long ago in the deer-haunted forests of Maine, when deep upon mountain and plain lay the snow.
The machinery by which these various processes are accomplished is exceedingly fine and worthy of notice, and vastly superior to that used in England; in the dock-yards of which country the circular saws were first brought into service, if we do not err especially that for cutting the teeth, which, worked by Steam-power, does its duty with great rapidity and incomparable precision.
This operation is performed by the vertical descent of a ponderous arm of iron, terminating in a cutter of the form of the notch to be made in the yet soft and smooth edge of the circular plate, which is made by the same power to revolve horizontally upon an axis placed at such distance from the impinging weight as the depth of the notch to be cut requires, and traversing at a rate so timed in unison with the descent of the cutters as to render the series of teeth perfectly continuous and equal; each blow of the cutter forming the interval between two teeth, and each full revolution of the plate completing a circular saw. In the same way is effected the teething of the straight saws, the motion being a direct sliding action in a forward line, instead of a rotatory movement.
In the English saw-works, owing to the influence of trade-unions, operative-unions, and the like, the application of steam-power to this machinery is prohibited, aud the employer is restricted to the use of hand labor-the cutter being jerked down by man power, and the edge of the plate to be cut being subjected to the striker by hand, the formation of the teeth not being regulated by any absolute scale, but being executed by the calculation or guess work of the artisan, and, of course, varying in accuracy, depth and precision of cutting according to the skillfulness-; or unskillfulness of the individual operator
To the absence of these ingenious combinations, injurious alike to the true interest of operators and employers, the superiority in many respects of American to English machinery is in some degree due; and not less to the over stringency of the patent laws of Great Britain, which often prevent the application of really 1eading and most material Improvements, of a radical nature, to principles secured for the benefit of the inventor. We may here observe that the use of circular saws is very greatly on the increase in this country, more especially in the western portion of it. In the east, for some inexplicable reason, this admirable instrument is far less generally used; and the writer of this article, several year ago, when on a visit to the timber districts of Maine, on expressing his surprise at the non-adoption of this most excellent and labor saving tool, could learn no adequate cause for the prejudice existing against it, unless it were some crude and absurd ideas concerning its vibration and consequent irregularity of cutting-objections not founded on facts, nor confirmed by experience.
From the saw shop the circular plates, now teethed and in the incipient stage of what Willis would call sawdom, are removed across Broome Street into the other building, and introduced to the saw-hardening' room, where they are converted into highly tempered steel. iron hardening This process is effected by heating the metal in charcoal furnaces to a white incandescent glow, and then cooling it by immersion in baths of oil and other drugs, the combination of which is, we believe, a secret.
This done, the saws are ready for grinding, which is effected in a special apartment of the main building-the fiat, straight saws by hand application to a series of powerful grindstones, driven at a regular speed by gearings worked from the engine and the circular saw, by a very curious and effective patent machine, peculiar to this establishment, and invented by Mr. Hoe himself.
The old method of grinding circular saws, and that still practiced in all other works of this nature, is the application of them horizontally to the great vertically- moving grindstones by the hand; and, when it is considered that these great steel plates run up to six feet diameter and eighteen at circumference, and that they consequently entirely conceal the grindstone from the eyes of the operator who applies them, it will be evident that the process is mere guess-work, and that no certainty can be attained in regulating the thickness of the blades-in a word, that nothing was effected beyond the superficial brightening and abstersion of the surface.
The new machine causes the great circular plate to revolve vertically on its access, while a "pad" to which is applied some sharp, detergent mineral powder, is moved forcibly over its surface with a triple action. In the first place, the pad itself is made to revolve' with great velocity against the circular plane, in a direction perpendicular to its line of motion. In the second place, it is driven forward against it horizontally with a force increasing or diminishing, in proportion as it may be desirable to render the saw blades thicker or thinner in any particular part of the circumference. It is usual to leave them thicker at the centre, and to grind them away gradually toward the circumference. Thirdly and lastly, the pad, while it revolves vertically in a direction perpendicular to the revolving plane, and is forced horizontal! y against it, is also driven laterally to and fro across its surface; and the result is a degree of equability, or graduation of thickness, as well as of superficial polish, scarcely otherwise attainable.
This machine is one of the special wonders and ornaments of the establishment. It will not be amiss here to add, that with the improvements of their manufacture the demand for circular saws is continually on the increase; and that a single house is in the habit of taking regularly six of these powerful tools weekly from the Messrs. Hoes' establishment. Returning hence to the leading and principal feature of these works, the manufacture, namely, of all the various instruments and appliances for the art imprimatorial, we are next ushered into the iron planing and cutting engine rooms, for the cutting the cogs of engine wheels, and finishing the surfaces of whatever portions of the machinery must be brought to a smooth and polished face.
This is done by the propulsion of the pieces of metal so to be planed, in a horizontal and longitudinal direction against cutting edges, which again move horizontally across the moving planes, and are pressed downward on them vertically, so as to bring the planing to the requisite depth. The abraded portions are thrown off from the surface, of cast iron in a sort of scaly dust, from wrought iron in long, curled shavings, and the planes' can be wrought up to almost any desirable degree of finish and smoothness.
The cutting engine for the formation of cogged wheels, bears some relation to that for the teething of saws, the cutter impinging downward, with an action in some degree intermediate between that of sawing and filing, upon the exterior circumference of the circular wheels, which revolve on their axis under them in a rotation so regulated to the fall of the striker as to insure absolute equality in the width of the cogs or projections.