Cylinder

“ A B (fig. 4 of Plate 20) is a hollow cylinder, of a diameter proportioned to the effect wanted to be produced. C is a cylinder closed at both ends, which fills that just mentioned as far as the length goes, excepting a play of about 1⁄8 of an inch. This interior cylinder revolves in the former; but not on its own centre. It revolves on an axis E eccentric to itself, but exactly concentric with the outer cylinder A B. The centre therefore, of the inner cylinder C, describes a circle within the outer one, which is always parallel to its circumference. ”

“ To each cylinder a pair of similar nickel bands are led downwards from the top of a casting which is bolted to the frame. The lower ends of these bands pass round the under side of the end portions of the cylinders, wrapping close round them, and are firmly attached to them. To the bottom of each cylinder is rigidly attached a heavy solid cylinder of lead, and these are the regulators of the position of equilibrium of the cylinders when they rotate under the action of the load. ”

“ Cylinder-printing is a much more rapid process, conducted by means of a brass cylinder with the pattern engraved on its surface, which is made to revolve against another cylinder covered with flannel, and charged with color from a trough into which its lower part is dipped. The calico is passed over a large cylinder made to revolve in contact with that on which the pattern is engraved, and which is charged with color from the one below it. Fig. 1 shows this arrangement, a being the large cylinder with the calico round it, b the engraved cylinder, c the color cylinder, and d the color trough. ”

“ The large cylinder being put in motion, the form of types thereon, is—in succession—carried to four or more corresponding, horizontal, impression cylinders, arranged at proper distances around it, to give the impression to four or more sheets, introduced one by each impression cylinder. The fly and feed-boards of two of the impression cylinders are similar to those on the well-known double cylinder press ”

“ In the first place, I remark that a cylinder carrying only its own weight and having the maximum length, beyond which it will break, will, when supported either in the middle or at both ends, have twice the length of one which is mortised into a wall and supported only at one end. ”

“ The platform on which the cylinder rests, carries the usual index. Rotation of the cylinder in a left-handed direction gives a reading for total reflection. A second reading is obtained by rotation of the cylinder in the opposite direction, the receiver being now at R′. The difference between the first and the second reading is evidently equal to twice the critical angle. ”

“ When setting a cylinder which is to be bored it should, when the design will permit, be set true by the outside of the flange, or what is even better, by the outside of the cylinder itself, rather than by the rough bore, in order that the walls of the finished cylinder will have a uniform thickness. The position of very large cylinders, while they are being bored, is an important consideration. ”

“ The workman buys a cylinder and whether the proper amount is cut away from the half shell, or the lips, the correct form is entirely ignored, and still careful attention to the form of the cylinder lips adds full ten per cent. to the efficiency of the motive force as applied to the cylinder. In making study drawings of the cylinder escapement it is not necessary to employ paper so large that we can establish upon it the center of the arc which represents the periphery of our escape wheel, as we have at our disposal two plans by which this can be obviated. ”

“ We will now take a solid cylinder, such that every inch of it is equal in bulk to half a pint of water, and plunge 4 inches of it into the water, so that the end of the cylinder [62] comes down to the 6-inch mark. Well, that displaces 2 pints of water. What becomes of them? Why, if there were no more cylinder, they would lie comfortably on the top, and fill the jar up to the 12-inch mark. But unfortunately there is more cylinder, occupying half the space between the 10-inch and the 12-inch marks, so that only one pint of water can be accommodated there. ”

“ If a cylinder move uniformly forward in the direction of its length, the resistance made thereto is not at all changed by augmenting or diminishing that length; and is therefore the same with the resistance of a circle, described with the same diameter, and moving forward with the same velocity in the direction, of a right line perpendicular to its plane. For the sides are not at all opposed to the motion; and a cylinder becomes a circle when its length is diminished in infinitum. ”

“ A cylinder should be so balanced that it will come to rest at any point. In a rough way a cylinder may be balanced by placing the journals on two carpenter’s squares laid on saw-horses. Gently roll the cylinder back and forth and every time it stops, make a chalk mark on the uppermost bar. If the same bar comes up three times in succession it probably is light, and a wedge should be driven under center band at chalk mark. Continue experimenting until cylinder will come to rest at any point. ”

“ The motion for working the cylinder, if an independent one, should be rigid and strong; for if there is any spring in it, though the cylinder may be brought in sufficiently close when there is much cutting on the card, if a blank card or one with very little cutting on it comes on, the extra pressure on the needles, especially with a large machine, may prevent it from getting in sufficiently close to clear the hooks from the griffe. ”

“ It appears, therefore, that there is a constant force acting on the inner cylinder tending to draw it into that one of the outer cylinders from which its potential differs most.
If be numerically large and comparatively small, then the force is approximately
so that the difference of the potentials of the two cylinders can be measured if we can measure , and the delicacy of the measurement will be increased by raising , the potential of the inner cylinder. ”

“ Cylinder machines are invariably used for duplex, triplex, and boards of several layers other than paste boards and those already described. Instead of a travelling wire, a wire-covered cylinder is the means of forming the film of pulp. The cylinder revolves in a vat of pulp, takes up a thin layer of the fibre, and, pressing against a travelling felt, leaves its film of paper, and as there are several cylinders, each in its own vat, producing paper in the same way, the several webs are brought together, rolled, dried, and reeled. ”

“ A cylinder of wood, inlaid with pieces of looking-glass, is fixed 'between two uprights, and made to revolve by means of a small crank and wheel, to which a line is attached. The netsman, retiring to some little distance, keeps the cylinder in constant motion by pulling the line, at the same time keeping up a soft whistling noise with his mouth. ”

“ We have now given minute instructions for drawing a cylinder escapement in all its details except the extent of the banking slot of the cylinder, which is usually made to embrace an angular extent of 270 degrees; consequently, the pillar of the cylinder will not measure more than ninety degrees of angular extent.
There is no escapement constructed where carefully-made drawings tend more to perfect knowledge of the action than the cylinder. ”

“ To remedy this inconvenience, when the wooden cylinder is placed within the tin one, in such a direction that all the holes are completely open, Dr. Darwin recommends a piece of the tin cylinder, about an inch and an half in length, and half an inch in width, to be cut out from the extremity of each hole next to the end B, and such piece to be fixed by a few sprigs on the wooden cylinder, exactly in the same place it covered previously to its being cut out of the tin one ”

“ Drying Cylinders.—These cylinders, by the same firm, for which patents were obtained in 1872 and 1887, are made with concave and convex ends, the latter type being shown in Fig. 44. The cylinder body is made [186] of hard cast-iron, turned and polished on outside surface. The ends and trunnions are of tough cast iron, turned to fit into their places, and there secured by bolts and nuts by a patented method, whereby no bolts (excepting for the manhole) are put through the metal, an unbroken surface is preserved, and the annoyance of leakage through the bolt-holes is avoided. ”

“ A “right cylinder” is the solid traced out by a rectangle which revolves about one of its sides, or the curved surface of this solid; the surface may also be defined as the locus of a line which passes through the circumference of a circle, and is always perpendicular to the plane of the circle. If the moving line be not perpendicular to the plane of the circle, but moves parallel to itself, and always passes through the circumference, it traces an “oblique cylinder.” The “axis” of a circular cylinder is the line joining the centres of two circular sections ”

“ When the hinder parts of bodies are of different forms, the resistances are different, though the fore parts are the same. Hence the resistance to the fore part of a cylinder is less than that on the equally flat surface of the cone or hemisphere, owing to the shape of the base of the cylinder. ”

“ This shows that there are two branches of the curve; the upper one does not pass through a maximum, but the lower one does.
(7) A cylinder whose height is twice the radius of the base is increasing in volume, so that all its parts keep always in the same proportion to each other; that is, at any instant, the cylinder is similar to the original cylinder. When the radius of the base is feet, the surface area is increasing at the rate of square inches per second ”

“ This I will put into a sort of square cylinder, or well, closed at the bottom somewhat like the breech of a gun. The block of steel fits so closely in the square well that no air or powder gas can pass it. ”

“ A prism or solid cylinder of glass, steel, wood or other breakable material which is capable of sustaining a very heavy weight when applied longitudinally is, as previously remarked, easily broken by the transverse application of a weight which may be much smaller in proportion as the length of the cylinder exceeds its thickness. ”

“ The cylinder was a circular beam of acacia or palm, upon which a mat or strip of cloth of some kind was nailed. By means of coils60 in the groove at the side the cylinder could be made to revolve, and the curtain would thus be easily drawn up and down. These curious forms are thus at once accounted for if we refer them to the wooden structures which were once plentiful but have now disappeared. Nothing could be more difficult than to find an explanation of them in forms appropriate to stone or granite. ”

“ The roughing cylinder carries a coarse grade of sand paper, and the finishing one a finer grade. They may be driven in opposite or in the same direction, as may be necessary. The lower frame is hinged at each end to the upper frame, so that by removing a pin, either cylinder can be reached by raising the frame with the screw and worm gear, operated by a hand wheel at the end of the machine. ”

“ A cylinder about an inch diameter, and six inches long, exceedingly truly bored, has a solid piston accurately fitted to it, so as to slide easy by the help of some oil; the stem of the piston is guided in the direction of the axis of the cylinder, so that it may not be subject to jam, or cause friction in any part of its motion. ”

“ The original form was a cylinder, which was changed to an ellipse, with the long axis in a horizontal direction, then into the shape of the letter D with the straight line undermost, and lastly into a semi-cylinder, with its horizontal diameter 22 inches, and its vertical varying from 9 to 12. The kidney form was at one time preferred, but it has been little used of late.
The form of retort represented in fig. 483. has been found to yield the largest quantity of good gas in the shortest time, and with the least quantity of firing. ”

“ The Refracting Substance.—For substances which can be cast, the molten mass is poured into a cylindrical mould with a thin partition in the middle. In this way two equal semi-cylinders are obtained at each casting. Substances like wood or stone are turned, and the cylinder sawn into two equal halves. In my experiments different sized cylinders were used. I have successfully used small ones with a radius of 8 cm. only. But when the cost of the material is not prohibitive, it is advisable to use fairly large cylinders. The cylinders used in the following experiments were 27·4 cm. ”

“ Lateral area is the area of the side wall of a cylinder. The pattern of the side wall of a cylinder is a rectangle whose length is equal to the circumference of the profile, and whose height is the height of the cylinder. The area of the pattern is equal to the length times the height; therefore, the lateral area of any cylinder must be equal to the circumference of the base times the height.
Problem 5A.—Compute the circumference of the chimney tube, Fig. 42, and compare the answer to the length of the line of stretchout between points 1 and 1. These should agree or a mistake has been made. ”

“ If we conceive a hollow cylinder made up of a great number of very thin layers—for instance, of wire wound on with a definite tension—in which case the inner layer would represent the bore of the gun, then the distribution of the internal stresses and their magnitude would very nearly approach the ideally perfect useful stresses which should exist in a homogeneous cylinder ”