Graham's Magazine, Vol. XLI, No. 5, November 1852. Various

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СКАЧАТЬ is accomplished by a set of change gears, which accompany the machine.

      The changes are made in the opposite end of the Crank Shaft.

      It will be observed that one revolution of the crank bears the same relation to the number of teeth in the large wheel, as one tooth in the wheel to be cut bears to the whole number it is to contain. The number of teeth and the pitch of the wheel is consequently derived from the change gears.

      When level gears are cut, the head is then set at the proper inclination, and secured by the screw which projects at the rear of the head.

      The cheapness of this machine more particularly recommends it, the price being but $250, while its efficiency and regular operation are so well established as to require no further comment.

      This is another admirable engine for diminishing and simplifying human labor. It is applied to the boring of all kinds of iron-work for machinery.

      The perpendicular drill, as will be readily observed, is worked with a swift, rotatory movement, by means of the bevil gears at its upper extremity. By a wheel – the circumference of which only is displayed in the cut – acting upon the thread of a screw midway its length, it is pressed down upon the piece of work to be drilled.

      This piece is secured upon a horizontal table placed under the point of the rotary drill, which table may be elevated or depressed at pleasure, by aid of the small lever projecting backward, which acts on a geared wheel playing on the thread of the great perpendicular screw of the main shaft.

      The nature, operation, and application of power in this engine are precisely similar to those shown and explained at No. 2. But it is employed only for the cutting of screws and screw bolts, and the boring of plates, pulleys, etc., which latter operations it performs by aid of Fairmen’s Universal Chuck, which will be described hereafter. In working this lathe, the implement last named is attached to the spindle, immediately under the right hand of the operator.

      The engine itself is of unusual neatness and finish.

      This little engine is similar in action and principle to the cut, No. 1; the iron, to be planed, moving horizontally and longitudinally on a bed, across which the cutting edges move with a downward pressure and a lateral movement, cutting and finishing the surface to the requisite depth and degree, easily and almost to perfection.

      The machine works very simply, and almost noiselessly; it is exceedingly handy, and is directed by one person; is very portable; occupies but an inconsiderable space, and does work precisely of the same description as No. 1, though of inferior dimensions in all respects.

      A Chuck generally is explained as being a round plate, which is fastened on to the spindle of a lathe – see No. 5 – and is used to bore holes in round or variously shaped plates of metal. It will be observed, in the cut above, that all the upright studs converge toward the centre by one motion of the lever, so that the centre of the article to be bored must correspond with the centre of the spindle. Besides all sorts of plates, as above mentioned, the centres of gear wheels and pulleys are bored by it.

      There is a beautiful principle involved in the action of this chuck, though its novelty is in some sort lost in its simplicity. Here, by a simple movement of the hand, the article to be worked is brought to its proper position; while, by the old method, the same position could only be arrived at after a series of trials; nor, in the end, is the article so firmly held, after its correct place shall have been ascertained.

      The last representation we shall offer to our readers is the subjoined cut of an improved borer for the wheels of railroad cars. The extreme simplicity of its general arrangements is its most conspicuous feature, and the small space it occupies is another highly important consideration. It will chuck all sized wheels up to three feet diameter, and can bolt on wheels of yet larger dimensions.

      In the cut, a car-wheel is shown set on the machine; the upright spindle which passes through it contains the cutters, and is driven by the pulley shown on the left side of the machine, which gives to the spindle-lathe its rotary and alternate motion.

      The brief account here given of these very ingenious and simple machines will, it is hoped, answer the desired end of conveying to the general reader some idea of the principles of operation, the perfection, and the immense general utility of these most emphatically labor-saving engines.

      We say emphatically labor-saving, because they not only spare and simplify labor by their own direct operation, but indirectly do so fifty or a hundred fold, because they are applied to the creation of those vast space-and-time-annihilating machines, which in the present day surpass the wildest and most marvelous legends of Fairy-land, of necromancers and magicians, as to the powers – incalculable and almost ubiquitous – which they bestow on their possessors, and which create wealth for the countries having sons expert to invent and use them, surpassing the gold of Ophir, and the gems of Golconda.

      FORGOTTEN

        Forgotten! ’tis the sentence passed on every thing of earth;

        Naught can escape the heavy doom, that in this world has birth;

        The cloud that floats in azure skies, the flower that blooms so bright,

        The leaf that casts a cooling shade, unnoticed pass from sight.

        – Forgotten! can it be that all, the beautiful, the good,

        The wise, the great, must buried be, ’neath Lethe’s waveless flood?

        Must all this world’s magnificence, its splendid pomp and pride,

        The fanes which man has proudly raised, and Time’s strong arm defied,

        Oh! must it all return to dust, and from remembrance fade —

        Will no faint memory remain, no thought, not e’en a shade?

        Alas! it must; thus has it been – thus must it be again;

        Who reared the lofty pyramids? Their work was all in vain!

        Stricken with awe, we gaze upon those monuments to fame,

        And ask, but ask unanswered, for the mighty builder’s name!

        The countless tumuli outspread upon our western lands,

        Who piled their shapeless forms, and why? Where are the busy hands

        Which ages since heaped high those mounds? Alas! we ne’er can know;

        Their names were blotted out from life long centuries ago.

        And must I be forgotten thus? When earth sees me no more

        Will all this working world plod on as calmly as before?

        Will no sweet memory of me cling round some constant heart?

        Must all remembrance of my life from every soul depart?

        It must not be! Build me a tomb whose top shall pierce the cloud —

        Pile high the marble! set it round with stately columns proud —

        Rear me some fane, dig deep the base, outspread it far and wide,

        And write my name indelibly upon its gleaming side!

        Down! down! rebellious soul, not thus must thou remembered be —

        Not thus a world must ages hence be taught to think of me —

        Not thus would I be carried on by Time’s resistless flood;

        I would not be remembered with the great, but with the good —

        If in my heart one virtue live, one pure and holy thought,

        If in my character one high and noble trait be СКАЧАТЬ