notch, a, the pin is disengaged from the gab in at the end it lifts the rack by its own movement,, dication of pleasure till the song was finished, the eccentric-rod. 5. A screw-clamp. On turning the handle the screw thrusts upward against the holder, which, operating as a lever, holds down the piece of wood or other material placed under it on the other side of its fulcrum. 6. Scroll-gears for obtaining a gradually increasing speed. 7. A variety of what is known as the "mangle wheel." In this one the speed varies in every part of a revolution, the groove b, d, in which the pinion-shaft is guided, as well as the series of teeth, being eccentric to the axis of the wheel. 8. Another kind of mangle-wheel, with its pinion. With this, as well as with that in the preceding figure, although the pinion continues to revolve in one direction, the mangle-wheel will make almost an entire revolution in one direction and the same in an opposite direction; but the revolution of the wheel in one direction will be slower than that in the other, owing to the greater radius of the outer circle of teeth. and follows on the other side. 14. Another form of mangle-rack. The lantern-pinion revolves continously in one direction, and gives reciprocating motion to the square frame, which is guided by rollers or grooves. The pinion has only teeth in less than half of its circumference, so that while it engages one side of the rack, the toothless half is directed against the other. The large tooth at the commencement of each rack is made to insure the teeth of the pinion being properly in gear. 15. A mode of obtaining two different speeds on the same shaft from one driving-wheel. THE EAR-ITS USES AND ABUSES. (Continued from page 6.) SOME canary of mine, since defunct, was very partial to my clarionet, seeming to derive comfort from a 9. Another mangle-wheel. In this the speed plaintive air, and eyed me from his perch, but at is equal in both directions of motion, only one circle of teeth being provided on the wheel. With once sought the bottom of his cage if I played a all of these mangle-wheels the pinion-shaft is loud, quick measure. His demise took place one guided and the pinion kept in gear by a groove day at dinner time, to the inexpressible grief of in the wheel. The said shaft is made with a universal joint, which allows a portion of it to have the vibratory motion necessary to keep the pinion in gear. 10. A mode of driving a pair of feed-rolls, the opposite surfaces of which require to move in the same direction. The two wheels are precisely similar, and both gear into the endless screw which is arranged between them. The teeth of one wheel only are visible, those of the other being on the back or side which is concealed from when it uniformly returned to the dovecot." These Toujours gai, toujours gai, remarkable for containing in its walls the glands of ear wax. one of my little ones, whose sobs refused comfort, deriving a post satisfaction from the decent interment of the bird within sight of the garden window. "The faculty of imitating sounds possessed by certain birds proves that the hearing must be exceedingly delicate, and though we suspend our belief of the great musical talents which some birds are said to have derived from education, we find many well attested instances of a delicate ear in species by no means remarkable for vocal execution." Madame Piozzi gives an account of a tame pigeon, which answered by gesticulation to every note of a harpsichord. As 12. What is called a "mangle-rack." A con- often as she began to play, the pigeon hurried to tinuous rotation of the pinion will give a recipro- the concert with every indication of rapturous cating motion to the square frame. The pinion-delight. A false note produced in the bird evishaft must be free to rise and fall, to pass round the dent tokens of displeasure, and if frequently rejection of a stream of water into the ear, and view. 11. The pinion, B rotates about a fixed axis and gives an irregular vibratory motion to the arm carrying the wheel, A. guides at the ends of the rack, This motion may be modified as follows:-If the square frame be fixed, and the pinion be fixed upon a shaft made with a universal joint, the end of the shaft wi describe a line similar to that shown in the drawing around the rack. 13. A modification of 12. In this the pinion revolves, but does not rise and fall as in the former figure. The portion of the frame carrying the rack is jointed to the main portion of the frame by rods, so that when the pinion arrives peated, it lost all temper, and tore her hands. "A The colour varies from pale straw, as darkness of mahogany and the hardness of old in the infant, and of a honey consistence, to the india-rubber. I have often taken an hour for its removal with the result of restoring hearing. And here let me make a digression on the common and indiscriminate use of the syringe. If there is pain in the ear it should not be thought of; great injury as well as intolerable agony might result. Should the ear passage be impacted the speculum is of no use, and a cautious removal of the plug is all the more necessary, for it may become moulded to the drum, and even inflame it. I have seen an old person faint from the violent inviolent cough or vomiting may be equally unpleasant. One portion of the ear passage is so intolerant of touch that a probe moved over it will cause the sensation of nausea; why, I believe anatomists are ignorant of, although compelled to accept the fact they cannot explain. The tube of the ear in most persons is not straight, and it becomes necessary to stretch the auricle backwards and upwards to see the membrane; some, on the contrary, have the passage so large that the membrane of the drum is seen without difficulty. The direction of the meatus, cious enough in all conscience, has his external however, as long as there are people who like seems to be for the facility of, catching sounds, ear passage expanded from behind into a circular such devices they will be paraded. It requires a addressed as they usually are to the face. In aperture, and his ungainly appropriations are nice sense of touch to be able to hit the passage animals, where hearing is necessary for their thus favoured. To strengthen the assertion of with a proper catheter, the bubble heard being safety, things are otherwise ordered; take the the hare's deficient hearing in advance of her, the your test of success. Attached to the drum memhare for example, Fig. 9, and also in the pole-story is told of one pursued by greyhounds along brane is part of one of the chain of ear bones, a cat, Fig. 10. Our ear passage is not of uniforma turnpike road; a woman was approaching im- truly wonderful structure, ever on the move; no calibre, but wider or funnel-shaped below, so mediately in front of her, she knelt down and the noise of clockwork here, balanced to a nicety, that in using the speculum it is only possible to hare ran fairly into her apron, which was stretched and retained in that balance by ligaments or binds see a portion at a time. The bony passage is in-out to receive her. This circumstance clearly to the bone walls adjacent. Every vibration is complete in the young, and in their case we get a proves that poor puss was much more occupied conveyed by this swinging chain of ossicles, or better view of the parts; what we see may be with dangers from behind, and heedle-s of those little bones, to the fenestrum, or window of the briefly described, and Fig 1 will convey some before her; she preferred, however, to yield her- vestibule, the fourth bone, or the third, according idea thereof. The first thing that attracts you if self to her who is ever the refuge of the perse- to some, closing that opening with a stopper you are sharp-eyed is a spot of white and a line of cuted and oppressed, and we may hope for the shaped like a stirrup. The hammer bone, Figs. white where the handle of the malleus or hammer credit of her sex she did forego the temptation 2, 3, and 4, acts on its neighbour the anvil, and bone is attached as if sewn to the membrane; you for once of roast hare and currant jelly. You this in turn on the stirrup, which is supposed to next perceive that the light shines off one part know, of course, that in the martial instrument be a compound bone. You can easily imagine that is higher than the rest, and if you look closely of percussion, provision is made for bracing up that if one of these bones was to be dislocated or and in a good light having a suitable ear for ob or tightening the drum-head. Well, the ear is servation, you may possibly be gratified to see provided with a tensor tympani muscle or one part of it vibrate; to do this, however, you stretcher of the drum, and as the hole in the inmust possess a Brunton's speculum, which magni-strument is supposed to be an air hole, so our fies the object, and a first-rate light. In colour cavity of the drum is supplied with one. Some the drum membrane is a mother of pearl white, contend that there is no analogy, and that the air like thin gold-beater's skin. It readily inflames, sent through the Eustachian tube from the throat then assumes a pink colour, at all times sensitive is to counterbalance the atmosphere and prevent to the touch, the slightest pressure causing pain concavity of the membrane. This tube, called and sickness. I believe it was Sir A. Cooper who after one Eustachius, opens into the throat beconceived the idea of puncturing the membrane, hind the soft palate, and performs a most iman operation that would require the nicest touch, portant function in hearing, for its closure is foland, after all, of questionable utility. Although lowed by deafness; its calibre is small, although surgeons might be numbered by the thousand, the opening in the bell-shaped extremity of the few have ever taken the trouble to see the ear-throat is large and wide; if the lining coat of dram, and I have seen some who considered it is inflamed, easy closure results, or it may be themselves very intelligent observers, direct the rendered more or less impervious by mucus filling tube of the speculum to the wall of the meatus, and it up. To remedy this defect a Eustachian cadescribe what was out of sight. Fine hairs line the theter or tube is devised to pass by the floor of passage, a cheveaux de frise in the face of an in- the nose into the bell muscle, and is connected trader. The adaptation of means to end is remark-with an air reservoir exhausted and closed by a able, and to be traced everywhere in nature; for in-stop cock; the connection being established, a jet stance, the ear passage in the owl is high up, just of air is forced into the cavity of the drum. In where he wants it-the hare's is directed backwards two instances death has followed the use of this with a long canal and highly movable ear, so that puss may be a match for her pursuers; the reverse obtains in the polecat, who follows his nose," and so deaf are they to what goes on at their back, that a story is told of a farmer who in trying to shoot one missed fire five or six times, and not a move was apparent on the part of the polecat until he was turned out of ie. The fox, preda elaborate machine, and its employment is per- thrown out of its joint, what mischief would ensue; the outer membrane of the drum is often destroyed, and impaired hearing results. That the ear bones are not an absolute essential of the hearing organ is evidenced by their absence in fishes; and in man the foramen ovale may be at times seen through the disrupted membrana tympani, and yet the relic of hearing remains, of course useless if the liquor Cotunnii (called after Cotunnus, an anatomist) is evacuated. A broken external membrane may be replaced by an artificial drum of Yearsley's, a neat little disc of indiarubber, wired, but if the inner membrane is gone, the "sanc um sanctorum" of the ear is invaded, and all is lost. Those of you who have seen boys lifting a stone with a leather sucker, get some idea as to the action of the artificial drum; it is the putting of a new patch on an old garment, or a patching operation like what we see on an old drum worn out in the vigorous service of a Punch and Judy proprietor. The vestibule into which the stapes is fitted communicates with the semi-circular canals and cochlea. See Fig. 1. The auditory nerve comes through the internal passage from the brain, and is in that opening said to be in close communication with the facial nerve, a fact of the highest importance in diseases of the ear. The vestibule I might liken to the hall of a house, the oval window being the door; it has no great vestibular proportions, being about the 8th of an inch in diameter. Numerous openings for nerves and vessels occupy the walls, and the apertures of the 1 sounds are still audible which result from the suc (To be continued.) CHAPTERS ON CURIOUS CATER PILLARS.-APRIL. BY J. R. S. CLIFFORD. a moth which frequently enters houses, and is as The caterpillar and chrysalis shown in our some of its habits are very curious. Indeed, much A rather odd caterpillar, not frequently found in gardens and orchards, extending itself usually WHEN vegetation, generally, has fairly duals attacked. Surely the most abundant of the April caterpillars, is that which produces the Winter Moth (Chimatobia brumata), and common as it is, surface of the ground, and the moth appears leaves. aquatic places, is that which includes the Wain- and deep black, the body dingy white, with black | required, that is, by means of the rack wheel on Many a young collector of insects has carried home with triumph the handsome caterpillar of the Drinker Moth (Odonestis potatorin), which feeds on grass in the early morning throughout THE WAVES. LECTURE was delivered at the Midland a heavy body acquired in falling through a depth equal to half the virtual depth of disturbance. The periodic tidal wave, the effect of waves upon the coast, the concentration of the energy of the wave upon being compressed into a channel, when its height became considerably increased, and the breaking up of the wave by an abrupt diminution in the depth of the water, were treated by the lecturer. In connection with the behaviour their refraction and reflection were noticed, and the lecturer, announced in conclusion, that his next discourse would be an explanation of the action of waves as regarded the stability and repulsion of ships. the spring, but not unfrequently during the day, A Instituts, Birmingham, on the 21st uit., by of the waves upon rolling in towards the shore, it climbs up some neighbouring twig to bask in the sunshine, leading persons to the natural, yet erroneous conclusion that it eats the plant on which it is found. This caterpillar is coated with hair, even to the feet, and is thus well enabled to defy the cold of winter. The colours are very varied, the back being blue-grey, mottled with black, with orange spots and streaks along the sides. The cocoon is formed of silk, and is of a leathery texture, and attached to a blade or two of grass. The name "drinker" was given to the species because the caterpillars have a habit of occasionally sipping the dew drops, and if kept in confinement, get on all the better if the food given them is damp, contrary to what is the case with the majority. Mr. W. J. Macquorn Rankine, Professor of Engineering and Mechanics in the University of Glasgow, on "Waves." The lecturer said he was not going to lecture upon those classes of waves, the existance of which was inferred by means of scientific reasoning, such as light waves, nor upon that class of waves whose existence, though a matter of demonstration, was not obvious to the senses, like sound waves; but the waves upon which he was about to speak were those commonly understood as liquid waves, like the waves of the sea. The motion of such waves was a subject which possessed a great deal of scientific and practical interest, inasmuch as it was against these waves that a defence had to be provided in the shape of breakwaters and sea walls, and a knowledge of their motion and the force they exerted was of great importance in civil engiBLANE'S IMPROVED MACHINE FOR neering relating to such works. Their motion affected in an important degree the motion of vessels, the stability and resistance of ships, and the power required for their repulsion. Therefore, a knowledge of the motion and the force exerted by waves was of the greatest importance in naval architecture and ship-building. The present lecture would embrace an explanation of the nature of the motion taking place in the waves of the sea, and the force they exerted. The MORTISING TIMBER. THIS HIS improved machine for mortising timber, patented by G. N. Blane, of Glasgow, consists of an upright framing or standar to which the moving parts are attached. The moving parts consists of a foot lever attached by a pin joint to the lower part of the framing or standard, and from the back part of such lever a connecting rod passes up and is connected to another lever at the upper part of the framing or standard. This lever is carried on a centre or centres fixed in the framing or standard, and its front end is connected by links to the bar which earries the mortising tool or tools. Below the mortising tool or tools an adjustable table for carrying the timber to be mortised is situated. Fig. 1 is a front view, and Fig. 2 a side view of the machine. A, the upright framing or atandard; Al, the foot lever; A2, the upper lever which is made forked, motion being communicated from the foot lever Al to the upper lever A2 by a back red; B, spindle for the mortising tool; C, tool in spindle; D, handle for reversing the spindle and tool; E, spring catch to keep the spindle in the proper place when it is rereversed; F, gauge to move to any depth of wood and keep the wood from lifting when the spindle with the tool is rising; G, pinching pins to fix the gauge to any height; HL, screws for shifting the table in or out from I te J; K, wheel to lift the table up or down to any height K H S THE MANCHESTER INSTITUTION OF ENGINEERS. OME three years since Mr. William W Hulse, M. Inst, C.E., and several other. eminent engineers of Manchester, perceiving the want of a good local institution for the advancement of engineering science, formed themselves into a society under the above title. The early proceedings of this institution have lately been The names of printed, and are now before us. those gentlemen who have taken an active part in the working of the institution indicate the value of its proceedings to engineers generally. A combined knowledge of the thoughts and ideas of practical men engaged in the various departments of mechanical science, helps greatly to qualify an engineer for general practice. It is to this end that such institutions are formed, and they are worthy of every support, whilst they are devoted to the mutual exchange and diffusion of the knowledge acquired by members during the pursuit of their respective branches of engineering. Turning to the "Transactions," we find the first part comprises the address of the president for 1867, Mr. George Peel of Manchester. After referring to numerous matters of interest, the President expresses a hope that it will not be long before a professorship of engineering is endowed in Owens College, and a professor appointed for instructing the pupils in that branch of scientific knowlege, which is one of the most important-in a practical point of view-to which they can apply themselves. The establishment of such a professorship would undoubtedly prove of considerable interest to all connected with engineering. The next meeting reported was occupied by a paper on dead stroke power hammers, by Mr. James Fletcher, Jun., and another on life boats and their appliances, by Mr. J. Corbett. Both subjects were fully discussed at a subsequent meeting. The remaining papers in the volume under notice are respectively on friction breaks and couplings, by Mr. T. A. Weston, aud on patent fuel, by Mr. G. W. Ommaney, The second part of the proceedings opens with the presidential address of Mr Hulse, who is termed the father of the institution. Mr. Hulse offers some very practical remarks upon the subject of light railways. [The same volume contains no less than five papers upon the Irwell floods, with suggestions for their remedy. Two of these papers are by Mr. J. Fletcher, the others being by Mr. G. Lowry, Mr. J. Corbett, and Mr. Trapp, respectively. The proceedings for 1869 are not yet printed, but an important paper on the patent laws, read by Mr. Theodore Aston, at a meeting of the institution held on the 4th of January last, has been published. The reading of this lecturer then popularly illustrated by means of paper is peculiarly opportune at this time, as the diagrams the way in which the waves were origin-subject of the patent laws is likely to be discussed ated, by some foreign body pushing the particles in the House during the present session. In this of water in a forward direction, when they became paper, and also in the discussion which followed heaped up, which direction they communicated to its reading, and in which several gentlemen well the particles immediately beyond them; but, in qualified to deal with the question, took part, will returning to their original level, they lost their be found some sound suggestions upon the whole forward motion. The action of the wind upon subject. We have only to add that the the water formed a long ridge, which, however, institution is represented in London by Mr. W. was not a continuous advancing motion, but an Lloyd Wise, who is the honorary secretary, and alternate rising and falling of the particles. In who has promised to furnish us with copies of the the most simple kind of wave motion, the papers read at the meetings of the institution, particles of water advanced and retired, each and which, if they correspond with those that individual particle describing a circle in about a have preceded them, will prove very interesting central position, by a series of crests and troughs. to our readers. This was the motion of the long Atlantic swell, and such waves had been known to travel 2000 miles with but little diminution in size. The modification which this wave motion underwent according to the depth of water, and the production of stationary waves, were illustrated. The speed with which the crest of the wave moved forward the lecturer explained to be the same as THE TRUE VELOCIPEDE. DCheshire, has published his paper read in tific principles which should guide in the construction of velocipedes." Starting on the assumption that, with a properly made velocipede, and on level roads, an economy of time and power is gained, Dr. Clarke adverts to the delusion entertained by many mechanics, that power may be created by mechanical aids. Our subscribers are tolerably familiar with some of the contrivances produced by such personsmachines with any number of toothed wheels and pinions, each additional complication entailing a loss of power rather than a gain. In the construction of, bicycles and other locomachines, the principles to be chiefly borne in wind and acted on are safety, simplicity, and eapness. The medium must be sought between Hightness and strength, the loss by friction must be reduced to the lowest point, and the power be applied to the wheel as directly as possible. As also there are two sets of independent muscles in the human body-one below and one above the waist-it is essential that, in a properly constructed machine, the two sets shall be able to act either independently or combined. These and other objects appear to have been kept in view by Dr. Clarke in the construction of the machines invented by him, drawings of which are given with his book, and which we reproduce. THE TRUE VELOCIPEDE. drums or pulleys on nave; & handles to pulleys; | in diameter, its bed twenty-one and a half feet foot-crank. Fig. 1 and 2 are a plan-view and a side- THE BROADWAY PNEUMATIC TUNNEL, drawing of a tricycle of a superior description to carry four-two men sit over the front wheels, a third over the back, and the fourth in a cushioned seat in the middle; though the single wheelWE give a series of engravings illustrating In Figs. 1 and 2 a are the saddles; b middle ON THE PHENOMENA OF COMBUSTION. this subject in the Lecture Room of the Society of Arts, John- |