SECK'S PATENT APPARATUS FOR CLEANING AND DECORTICATING GRAIN-Described on page 343.) Java; Nourouk, Mauritius; poukpin, Burmah (Butea, Connell, Killaloe, Plassey, &c., and then to take the rondosa). Pongamia glabra, E.I. Korung oil, India. Parkia biglanduloso, E. I.; 18 per cent. Also starchyielding plant. Ourala, opochala (Pentaclethra macrophylla), Gabon, Fernando Po, &c., good for culinary use, lubricating machinery, and soapmaking. 48 per cent. Oleo de Camaru, Brazil,Tonquin bean(Dypterix odorata), perfumery and medicine. Ben oil (Moringa pterygosperma), morunghy yennai, Tamoul; morunga noona, Teloogoo. Plant originally from Syria, introduced in the West Indies, oil very fluid, used by watchmakers and perfumers. Moringa apteria, Egypt. Omitted: Chalmogree oil, India (Gynocardia odorata) Arnatto Order, or Flacourtiaceæ. I did not mention a certain number of oils I found quoted in authors without the designations whether they are fat oils or volatile, and which I had not the occasion to examine; of several I could not define the botanical name. Such are the following:Nhan-pyai and Nhan-mai, from Moulmein. As we have yennai in Tamoul, noonay in Teloogoo, and unnay in Canarise for oil, I conjecture that "nhan" means oil in Burmese, and that the first is coming from Myet-pyal (Melastoma malabathricnm), the second Kunjee oil, from India. I think sesamum kunjed being the Persian name for sesamum. Surgoojah oil, India (Helianthus annuus, or sunflower), &c. I might have added many vulgar names, but this would have occupied too much of your valuable space, and my note is already rather too long. Happy shall I be if it should prove useful to some readers of our ENGLISH MECHANIC. Cassia sp. steamer down the lower Shannon to Kilrush and car meets facilities along his route which are not to be met with elsewhere. The Midland Great Western Railway Company, in its arrangement as regards time and fare, enters thoroughly into the requirements of the excursionist, and gives every opportunity of conveniencing those who travel along the lines under its control. The knowledge of this fact alone should fill the County Galway and the surrounding counties with tourists during the coming summer months. The trip to be sketched out for the tourist should of course depend upon the time at his command. The picturesque city of Galway should first be reached, and if possible the romantic islands of Arran, abounding in interesting ruins and covered with rare C. TOWNLEY, The Turret, Ballingarry, Co. Limerick. as Outerard or to the beautiful village of Cong at its ferns, visited. A sail up Lough Corrib, either as far "Now that a magnificent touring season is approach-northern extremity, must next claim attention. If ing, intending excursionists, whether preparing to the former place be stopped at, the visitor cau at once buckle on the knapsack and grasp the stout oaken proceed through the western highlands and enjoy onestick solo, or in parties, are anxiously looking out to of the most delightful drives it is possible to conceive. select an interesting locality as the scene of their Bal linahinch, celebrated for its marble quarries; rambles. As regards the inhabitants of this locality Clifden, for its natural beauties, are successively -of Clare, Limerick, Cork, and Tipperary-the entire reached, and a short tramp to the north of Clifden south of Ireland has been overdone. There is scarcely brings the tourist to the pass of the Killeries, one of a waterfall or a ferny nook, from the Slaney to Dingle the most gloomy and terrific pieces of wild scenery, Bay, or from Crook Haven to the Shannon, which has mountain and ocean combined, that the British sight-seers. The beauties of the Blackwater are islets, is marvellously enchanting; and indeed along not been over and over again invaded by the feet of islands can produce. Clew Bay, with its thousand known to almost every one, and even exquisite Kil- this stern coast, almost at every headland, some new larney has to be ransacked in search of new scenes of feature, wild and wonderful, meets the astonished loveliness. It is to be deplored that while Ireland gaze. If time should not permit the tourist to proceed presents so many attractions to the tourist, that people beyond Westport, he can return by rail to Athlone, Scotland scenery far less gratifying than can be found pursue his course still farther north until he reaches will leave her shores and prefer seeking in Wales and or, better still, if he can prolong his rambles, he can at home. Windermere, fascinating as it is, can never Killala and Sligo, in which case his homeward route compare with the more awful beauties of the Kerry should be via Mullingar on the Midland Great Western lakes, and nothing that North Britain can show, emulates the grandeur and sublimity of the terrific gorge of the Killeries. Apropos of the Killeries and of that interesting county washed on its southern shore by the bay of Galway, and on the west by Clew and Sligo bays, and which stretches out to the north by Lake Erne, there is no district of such limited extent so fully capable of gratifying the curiosity of the traveller, or of satisfying his utmost cravings after new and beautiful scenery. The counties of Galway, Mayo, and Sligo, have been hitherto almost a terra incognita to us southerns. It was so tedious and so expensive to reach their scattered beauties that more time was expended in paying a visit to Lough Corrib and Connemarra, than would bring the tourist Wales. Fortunately all these things are now removed; through the different points of interest in South the opening of the railway communication from Ennis to Athenry, brings within a few hours' run of this city the starting point of as interesting a tour as could possibly be devised. Fortunately, too, the tourist line. This excursion, which includes most that is beautiful in the western highlands, might well be performed in from seven to ten days, and a tourist, who unites with a love of mere scenery, a taste for the beautiful in nature-the ferns which are hidden in wild mountain gorges, the heath which cover hillsides, or the singular geological features which present themselves continually before him-will find himself amply rewarded for his toil and travel." INTERNALLY-GEARED LATHE. my internally-geared lathe:-Fig. 1 represents the SIR,-Herewith I forward to you the drawings of 2 is a front elevation of the same, and Fig. 7 is a lonpulley and portion of mandrel in side elevation. Fig gitudinal section. in all the figures. The letters refer to the same parts through the boss on to the mandrel. A is a gun-metal wheel pinned which Fig. 2 is a front view, has on it five circles of This wheel, of holes-viz., 360, 336, 300, 144, and 96. The other side of it is an internally-cut wheel of 60 teeth. Figs. 3 and 4. This wheel gears into two wheels of 12 teeth, H and I, fitted upon the disc B. Figs. 5 and 6. The pulley C is of cast iron, and is bored to fit the mandrel easily, and is capable of revolution on it. On the projecting part of the neck of the pulley (Fig. 7) there is a plain part turned, over which the cast-iron disc B, is fitted loosely, and beyond this again is a small wheel K, of 12 teeth cast, which gears into the wheel I. D is a fine screwed nut, that binds the whole arrangement together when in single gear, and G is a hinged catch that is fitted into the headstock, and when raised falls into the notch J in the disc B. The action is as follows:-When in single gear the pulley and all its parts revolve as an ordinary one. the catch G is thrown out, and the nut D is screwed home. When the slow motion is required, the catch G is raised into the notch J, and the nut D is slacked back about 1 or 2 turns. The lathe cord being upon one of the grooves of the pulley C. revolves it, like wise conveying motion to the wheel K on its neck. This wheel turns wheel I, and I gears into H, which turns the internal wheel A, and so produces the slow motion by the difference of the number of teeth in the wheels K and A, which in this case is as 12 is to 60, or as 1 is to 5. The catch G is likewise very useful for blocking the mandrel stiffly (as in unscrewing a tight chuck); and as any part of it can be brought into position as regards the notch, it can be blocked in any part of its revolution by slacking the These drawings form full working drawings, being strictly to scale, 3in. to the foot. nut D. ASTRONOMICAL. G. W. A. The operation by five-figure logarithms would be quite sufficient. The geocentric longitude of Venus computed from Right Ascension 326 51'585, and declination 6° 4' 11" S. is found by the first formula to be 3260 59 47"-9, or 26 59 47-9 and its latitude 6° 51' 22/5 N. Using the last formula, and the logarithms to five planes only, we obtain the approximate result 26° 59/8 for the long. and 6° 514 for lat. Please show in the eliminated formula how to distinguish whether the lat. is N. or S. In the " Astronomical Notes for June" it is stated that the moon will be in conjunction with Mercury at 49m. past 2 a.m on the next morning; "a.m," should have been left out. Mars is in conjunction with Jupiter at 1h. 12m. on the afternoon of the 27th, 7h. 12m. is therefore an error. There is not given any account of the rising and setting of the planets for this month. Seeing that astronomers agree to compute from the first point of Aries, why do they not say that Jupiter is in Gemini, Uranus iu Cancer, &c., instead of telling us that the former is in Taurus, and the latter in Gemini, &c. If they intend to adhere to the ancient division of the Heavens, why do they make their computations from the point to be determined by the precession of the Equinoxes'? G. FIRTH. MUSIC. SIR,-Mr. Trayler (page 332) has earned the hearty thanks of "our" musical readers, in defending the sol-fa method, which has received some "hard hits " lately in your Answers to Correspondents. 1 can fully endorse what he has said respecting the advantages of this easy, cheap, and true system, having had the drudgery of teaching by several methods for the last twenty years. Let me state for the benefit of those who wish to sing correctly and easily, that I lately took a class of village boys, from seven to nine years of age, who, without any previous knowledge of music were able to sing ordinary hymn tunes at sight, after six lessons of half an hour's duration. Now if any of our readers can show me a "more excellent way," I shall be most happy to learn, and they will be doing good service to hundreds of others, by making it known in "our" columns. There is just one part of Mr. Trayler's letter, with which my experience will not permit me to agree; he says, that this method will teach pupils to sing in tune better than any other. I have always found that singing out of tune, is the fault of the singer's ear, and cannot be ascribed to any method of teaching. I am of opinion that no amount of practice will cure this evil, so trying and unendurable to a good "ear." I may add, the tonic sol-fa system number its adherents by tens of thousands in all parts of the civilised world-wherever there is competition, it is never in the rear-and is now too firmly established to be shaken by the prejudiced opinions of old notationists. A SUGGESTION. ¡MUSICUS. SIR,-If I, during the summer, go to Cornwall, Wales or Westmoreland, and wish for authentic information regarding the vicinity in which I may find myself, how am I to get it? I doubt not but many of your readers, if I knew them, or they knew me, would be pleased to offer their services, and tell me exactly what I wanted to know. Many others, situated exactly as myself, would gladly hail and reciprocate the kindness thus given. Could not some of your readers give their names and addresses, the time they could receive "calls," &c., thus, "H. B. 4 a.m.," " T. R., 8 a.m., 4 p.m. Any travelling English mechanician calling at these hours, would receive a hearty welcome, trustworthy information regarding lodgings, remarkable places, and general charges. C. H. W. B. SPORTSMAN'S VELOCIPEDE. SIR,-If you should think it worth engraving, I enclose a plan and elevation of a velocipede, the best I think, the querist (4097) can have for the purposes he requires. It is four-wheeled, and has a broad seat for A WORKMAN'S APPEAL. SIR, I like the letter under the above heading in your last number, because the writer exercises the Englishman's privilege of growling like a man, and admits his consciousness of the row he is making. Seeing, however, that his requirements range from mathematics without symbols, up to slide-rests of the third order of complication, and considering the great variety of subjects touched on in the letters you publish, it does seem odd that he does not more frequently find something to suit himself. May I ask him if there is any subject that he has ever heard of, about which he wants to know anything, and will not get a prompt answer about in the ENGLISH MECHANIC, from some one or other, if he will only take the trouble to say what he wants? Also, now that he has got the drawing of slide-rest, of what possible use it can be to him? Not to make one by for sale surely? Who would buy it if he did? for although Mr. Evaus gets £65 apiece for them, I think one of his would be preferred at even that price by any body wanting one. Also, I wish to refer Blacksmith" to two letters of the "Harmonious B." in Vol. X., one on forming steel mandrils, and the other on building a lathe under difficulties, and to ask whether such letters are not, as it were, specially for the class to which he belongs, although the information may not be what he individually wanted at the time? As regards self-teaching, it is one of the most laborious tasks possible, though there are plenty of helps for the purpose published Lowadays, without any more being written, and in writing those helps, the difficulty is to make it easy enough; just as in drawing up an examination paper, the difficulty is to keep it down to the level of the knowledge of the pupils, not to puzzle them with hard questions, which some folks look on as evidence of sharpness on the part of the examiner. But that men have taught themselves even high mathematics, was proved by my old tutor, James Hann, of King's College, London, who was once a pitman at Newcastle, and had charge of the windingengine at the pit-mouth, and worked his sums with chalk on the end of the boiler! and in those days there were very few rudimentary treatises to help any body. He tried astronomy first of all, and when he found he could not understand it from waut of kuowledge of mathematics, went back to the beginning, and never tired till he had learned it all, and made the best of masters, because, having laboriously gained every step 25 to an inch. or more accurately, 100 parts in 3.9 4in and measure with his rule on that scale, the number of millimetres, given. I quite gree with him, that to rush off to some book, and find a formula ready made for the job, and put the valves in for the letters, and stir them up till a result comes out, is not the way to answer a question to the satisfaction of a practical man; and it is the way only too often adopted by certain of your correspondents. It is like copying out a recipe without being able to write "proved" after it. J. K. P. A CUMBERLAND MINER'S APPEAL. SIR,-In answer to "A Cumberland Miner," allow me to suggest two methods of preventing those terrible explosions he mentions:-1st. Go to a clever blacksmith, and get brazed on to the end of the pricker with a slanting splice-a piece of copper a few inches long, so that it will enter the powder, and not the iron end of the pricker; but if the powder is likely to ignite even after the iron pricker that is now in use is drawn sufficiently out to be above the powder, then I suggest (2nd) that a brass tube lin. internal diam., and the proper length (and a piece sft. long can be got at Birmingham for about 6d. or 8d.) Have a piece of round rod iron diam. driven into it to within an inch of one end, which end may have a piece of brass or copper soldered or brazed into it, and pointed off to imitate the pricker at present in use. With such a pricker, the rammer, if it struck the pricker when the miner was ramming on the powder, would not strike a spark or fire, and the pricker would not bend like copper. H. W. A. S. SIR,-Let a "Cumberland Miner" take 1lb. of hog's lard and 2oz. of finely-powdered rosin, mix them at a gentle heat, and when using the pricking rod, smear a piece of paper (such as our MECHANIC is printed on) about 2in. wide, and whatever length the hole may be, twist it with a slight spiral direction round the rod, and place the hole in before tamping, and after the hole is stemmed or tamped, the rod will withdraw with safety. To thoroughly test the above, place a piece of the smeared paper on a piece of flint, and strike with a steel, and it will be found utterly impossible to obtain a spark, where the paper covers the flint. W. W. SIR, As I understand the "Cumberland Miner,' the operation of blasting is as follows?-The hole is drilled in the rock, the powder inserted, the pricker placed in the hole with the point in the powder, the hole is then rammed full of earth, &c., and the pricker withdrawn, leaving a smali hole for the insertion of the fuse or straw. The dangerous part of the work is withdrawing the pricker, as it may strike fire from rubbing against the rock. Now, I have heard it asserted that ramming the hole fall is quite unnecessary; that a wooden plug driven into the mouth of the hole is much more effective. This would appear to be correct according to theory, for it is well known that a gun barrel which would bear very heavy charges of shot, when rammed down on to the powder, may be burst by inserting a cork in the muzzle before firing. If the "C. M." would try the wooden plug and report the result, it would be interesting to your readers, including G. H. SIR, I have used a copper pricker for five years, and it is very little the worse for wear. We have a silicious grit so full of fire, that to use an iron pricker would be exceedingly dangerous; hence the use of the copper one. My beater or stem-rod is much thicker for an inch at the lower end, with a groove in it made with a round file, to admit the pricker. I preserve the dust that comes out of the hole during boring to stem with it or plate. Having bored the hole, I put what powder I think sufficient into it. Having slightly greased the pricker, I thrust it to the bottom of the powder, and put some paper on it to prevent any fire igniting it. After stemming 6 or 8in., I slightly draw the pricker, and so until the hole is stemmed. Care must be taken to keep the pricker straight in the groove of the beater. Attending to these directions, Ho accident such as he alludes to need be apprehended. A YORKSHIRE LEAD MINER. GOURDS. SIR, Your correspondent" Beta suggests that in formation regarding food must prove useful, especially if attention can be drawn to any members of the vegetable kingdom, whoss properties are mot generally known or understood. Acting on this, I will draw your readers attention to a vegetable, easily grown, and much used on the continent, but scarcely at all in England-I mean the gourd or pumpkin. 1ts culture is the simplest. On a small heap of manure or leaves, or anything which will give a little bottom heat, sow one or more seeds of the mammoth gourd. This, with an occasional watering, will produce fruit of upwards of 50 or 60 lbs weight. As a proof of this, two were exhibited last year at our local flower show, which grew on the same plant, and weighed respectively 87 and 42 lbs.-129 lbs.. from one seed. At another show were exhibited seven which weighed together 413 lbs. They are most excellent food for man or beast, either in soups, pies, or boiled as a vegetable, and as they are not gathered till ripe, and then hung up in a dry place, and a slice cut out when required, they are useful all through the winter. A packet of seed, price 6d, can be had of Messrs. Sutton, Reading. It is rather late, but I hope some of your readers will try them this season, and state to you the result. W M, G. NORTH OF IRELAND. concerning tourists' trips in Ireland, and finding that SIR,-Having read the letter in your last number, you are willing to insert further communications on the subject, I beg leave to send you the following. Donegal is well known as the most picturesque county in the North of Ireland. It is full of high mountains, and small romantic lakes. The Atlantic Ocean on three sides washes its grand and rugged shores, and many beautiful inlets penetrate far inland. As I am perfectly acquainted with the county, I can with confidence recommend the following tour as one that will repay the small time and expense necessary. I suppose a traveller to reach Belfast early in the morning by the steamer from Liverpool, Barrow, or Fleetwood. After rest and breakfast at the Imperial Hotel, proceed about 9 a.m. by the Northern Counties Railway to Portrush. The omnibus of the Antim Arms Hotel, one of the best in the North of Ireland, is waiting at the station. Spend that afternoon in a ramble on the rocky Dromon Head, and on the beach, which is only equalled by two others in Ireland. Next morning visit the Giant's Causeway (by stage from the hotel) and the grand cliffs beyond. Boats are always to be had, but if you object to rough water you can see almost as much by land. Sleep that night also at Portrush. Next morning take a car to Portstewart-3 miles, and there (for I address predestrians) begin your walk, keeping along the shore till you reach the mouth of the River Bann, which you will cross by a ferry. Still keeping by the shore, you will reach Magilligan, which is at the mouth of Lough Foyle. Cross there by ferry-boat to Greencastle-2 miles, and you are in the rugged County of Donegal; walk from Greencastle to Carndonagh, where you ought to spend the third night. Next morning, walk from Carndonagh to Buncrana, ascending Slieve Snaght Mount on your way, which is more than 2000ft. high, and commands a magnificent view. All that day's walk is most picturesque. There is a large and comfortable hotel in Buncrana. Next day take the rail from Buncrana to Fahan, and there cross the beautiful Lough Swilly to Rathmullan, theuce by mail cart to Letterkenny, where you would spend the fifth night at Hegarty's Hotel, a very clean and comfortable one. If your time is short you can end your journey here, and go by public stage next morning to Strabane in time for through trains to Belfast and Dublin. But if you have 3 days more, by all means wait, and take a post car from Letterkenny to Glen Beagh, the most beautiful spot in the county. You will also pass Gartan on the way, which is only second in scenery. At the lower end of Glen Beagh dismiss your car, and walk up along the beautiful lake, which is 3 miles long, lying between precipitous rocky mountains. If possible, get an active little boy to guide you across the mountains to the Piso Glen of Dunlewy. While crossing this pass, you will obtain a truly magnificent view. Below you are the Dunlewy lakes, and beyond them Erigal, rising precipitously, the highest mountain in Donegale and in the North of Ireland. Descending, and passing Erigal, make your way to Gweedore Hotel, and spend the 4th night there. After which you can either (1) spend a day at Gweedore, boating, fishing, and ascending Erigal, for which last you should take a guide; or (2) go by mail ear to Dunfanaghy and spend a day there, ascending Muckish, or exploring Hornhead; or (3) go by the same mail car through Dunfanaghy to Letterkenny, where your journey will end. Let me add, that if a Sunday should occur in your tour, you will find Portrush or Letterkenny the most agreeable places to spend it in, as they have the most comfortable hotels, the various places of worship close at hand, and the opportunity of pleasant short rambles in vacant hours. I I write without the opportunity of eonsulting local sources of information, or would add distances, times and fares. Let the intending tourist by all all means procure "The Highlands of Donegal," Murray, an admirable book, written by a native of the county. shall now only add two hints to travellers, (1) that it is necessary to ascertain particularly where you can get a good bed and breakfast, for Donegal is out of the beaten track for tourists, and you cannot count upon these; and finally, that a weary predestrian can at any small town hire a post car, at 6d. a mile for one. and 8d. for two passengers with a gratuity to the driver of a fourth part of the fare. H. S. L. SQUARING THE CIRCLE. SIR,-In the current number of our journal, is a very funny letter about squaring the circle by practical geometry. If Mr. Arthur Gearing starts with the parallelogram and divides it into cuneiform pieces, as represented, he will not be able to make a circle of them, but a polygon; on the other hand, if he starts with the circle he will not be able to make a paralleloram but a figure with wavy or serrated edges; it the circumference of a circle by means of a piece of puts me in mind of the carpenter's mode of measuring string. T. COOKE. tions of the circumference of the circle. Mr. G. transforms 36 sectional curve lines into a continuous right line as a side of his square! and he introduces a similar series of curve lines into the area of his square in contact with each other, so that it would appear, even to "ocular demonstration," if correctly drawn that a series of blank spaces remain unfilled, the con sequence is, that the area of the square is considerably larger than that of the circle. Mr. G, attempts to support his demonstration by a reference to the XIT which shall be equal to a given restilinear figure. Prop. of the 11th Book of Euclid :--To describe a sea! proposition cannot possibly apply to Mr. Gearing'e This conversion of his parallelogram (Fig. 2) into a square (No. 3) for the very obvious reason, that his parallelgram is not, and cannot be made into a rectilinear figure, no more that his square, because the sides are Either Mr. G composed of 31 curved lines each. deceived himself or he was not honest, in reducing these curves iuto straight lines, and in palming a false parallelogram and square upon the readers of the ENGLISH MECHANIC, and in attempting to establish reference to Euclid, his solution of squaring the circle by an unjustifiable It is to be hoped that Mr. Arthur Gearing will be more successful in his next effort to give an interest in the study of practical geometry by the mere exercise of ingenuity." WM. ARTHUR DARBY, M. A., F.R.A.S. Chorlton Hall, Manchester. COTTON SPINNING. SIR,-It appears I have succeeded in raising a ghost that is determined not to be laid until the "reason why" has been given. I trust you will kindly excuse me, though I cannot be sorry for it. However, I do believe that a little bit of consideration would have my first answer to Factory Lad," was as consistent convinced many of my cotton spinning friends, that an answer as, under the circumstances, could be conscientiously given to so simple a question on so important a subject, and one that involves so many considerations. When I answered the question at first, 1 had a fourfold object in view. The first was to raise this ghost, or the subject, in a manner that would thoroughly disturb it, so that it could not rest again until it had received its due. The second was to show the folly of asking for advice without stating plainly and fully all the circumstances bearing upon the case, and the danger of giving it also. The third was to show the "ads" a stumbling block over which they might easily flounder-" Factory Lad" saw this. My fourth was to call forth answers from other readers, that the subject might be fairly handled, and I had this object still when I gave my second answer. My motive may be open to censure for anything I know but I have papers by me here, in which I have tried to treat of the subject in as simple a manner as I could, to make it comprehensible to the "lads," and, by the way, if any one will try to do this, he will find it no easy matter; neither can it be done in one or two long letters, let alone short ones. I don't know how others find it, certainly, but I have to write, write, and re-write, before I can half satisfy myself that I shall be understood. But this is perhaps owing to my inaptitude, as I am but an entirely self-taught factory lad, barring, that I took all the houours of A. B.-abs by a nine months' half time attendance at a sort of hedge school. I have been driven from my first intention by the very ghost I raised, and this week I am glad to see that B. W. R." has taken up one part of the subject in much the same way as I intended to do, if others did not. Now I fully made up my mind last week, for "peppering "both" M. J." and H. C. S.," for what I felt to be ungenerous remarks. I cannot see what sense there is in any of us trying to make each other appear as simpletons, whether we do so by garbling or implication, when we are doing our best for each other, and for thousands of others. If " B. W. R." will refer to page 231, at the top of the middle column, he will see that he 18 mistaken-I hope he will kindly acknowledge. With respect to the two last letters of "H. C. S.," in which he refers to me, I protest, in the words of a country lad, ageanst ho'din' bulls whoilst other fooaks whollops um." But as soon as he has satisfied me that there is no "chaff" intonded in his last letter, I will give it due attention. I may nere say, in expla nation of what I said about putting the cart before the horse if he intended it to go, that I wished to suggest by what I said, as I thought it was opportune, the vagueness of the word "draw," as it implies something like attraction, whereas mechanical motion is communicated by impulse, or pushing; hence the horse pushes the cart before it by means of the collar on its shoulders, &c. In conclusion, I hope this epistle will do. omething to appease the wrath of the ghost I have raised, as I raised it with a good intention, but for, when I considered what little attention the subit kicked up a greater floundering thau I bargained ject of cotton spinning had called forth from correthe first number of our paper. "B. W. R." says I spondents before, and I have been a subscriber from appear to have lost one end. I hope he, "H. C. S.,' "M. J.," and "Factory Lads," ad lib., will try and prevent me from losing the other end. The "cotton panic" taught above one lesson, and I will give the results of experiments if others will do the same. 44 E. SLATER, Burnley. SIR. Mr. Arthur Gearing deserves great credit for his ingenuity, if not for his success, in his elaborate effort (No. 273, p. 301), to solve, even practically, the unsolved problem of squaring the circle." Mr. G.'s diagram presents certainly the nearest ocular solution of the great mathematical puzzle. Having arrived at SIR, Putting aside the preliminary remarks of this conclusion, it seems strange that the ingenious "B. W. R.," in last week's paper, let us at once come discoverer did not attempt to crown his work by conto the question, is it proper, in taking the draught of necting his diagram of practical geometry " with a a carding engine, to begin at the feed rollers? I say regular geometrical demonstration, proving the per- yes, and that the rule disputed is correct in that point. fect equality of the relative areas of his circle and B. W. R." says no; you must begin at the lap rollers, square. Had he done so he might fairly be entitled as there is a draught between them and feed rollers. to an "lo, lo, triumphe" in the columns of the My advice is, begin at the feed, and end at the deliENGLISH MECHANIC. It does seem a ruthless act to very rollers, except you want to see whether there demolish Mr. Gearing's "practical" or rather mechani- really is a draught between lap and feed rollers. If cal, geometrical square, but the interests of science there is, get it altered at once, as it is a greater evil demand it. If a square be "a four-sided figure whose than it is a benefit to give the slightest strain to a lap. sides are equal, and whose angles are right angles," If the rule I give is not correct, then all the authors I Mr. G.'s square is really no square at all, for two of have studied are all wrong likewise; for I never found its sides are not rectilinear, and, therefore, not equal one yet who commenced at the lap rollers to take the to their opposite sides; they are a series of curves-sec- draught. And yet they undoubtedly would have done so if they had any idea that there was one; or if they had thought a draught at all necessary. B. W. R." is just confounding theory with practice In his analysis of my letter last week. If he does, he will find them (in cotton spinning especially) very awkward fellows to deal with. He forgets we were dealing with the former, not with the latter. But even looking at it in the same light that he does, how does he account for a carding engine working with the same arrangement I quoted, with rollers covered with fillet instead of being fluted? Now, if mon ami does "happen to be acquainted with the make of the engines I took my figures from," he must bear in mind that machines do not always remain in the same state as that in which they are sent out, especially where there is machine making combined with cotton spinning, as in my case. The particulars I quoted last week were from one of Walker and Hacking's single carding engines, the only one we have. Ile is wrong in his statement about the length fluted rollers will take upat least in my case. I am aware it is a common custom to have very deep flutes cut in the feed rollers. Now, ours have not; consequently, there is very little difference between the theoretical and the practical results of the length taken up. In fact, what slight difference there was I got our carder to counteract it last week by nailing thin slabs of wood, fin. thick, round the lap roller, making it same as some of our other (Walker and Hacking's) double cards, the lap 11 48 rollers of which are 6in. diam. ·×90 14 61 In his illustration of the piece of string, does he mean to say that it would bag if it had a support in the middle same as a guide plate to a carding engine? If he will take a piece of string, and hold it tight (not extra tight) between two points 12in. apart, I am afraid that neither he nor any body else would be able to detect the slightest bag in the middle. Neither would he in a lap at that distance, if it is taken up as it is delivered. The result of what he says last week just amounts to this-that the draught of a carding engine should be taken from feed to delivery rollers, as at first disputed; for if you begin at the wheels on the lap roller, as in my case, it does not alter the theoretical result one jot, and that is what you are. dealing with. "B. W. R." says he does not consider his argument answered by what I explained. Well, cannot help it, but I am happy to say mine is. much obliged to him for his kindness in giving me the recipe for size, and also for his information on yarn testers. I heartily endorse all that he puts forth in his first letter, last week, on the draughts in drawing frames, in which he displays his thorough knowledge of the subject. It is really more than I can credit him for with regard to his pet ideas about the indispensable draught between lap and feed rollers. I am than that they were in a good balance, which is pos- THOMAS EVANS. [We have omitted certain offensive remarks from this letter, which if inserted would have irritated the correspondent alluded to, without producing any corresponding benefit. We are sorry after what we have said that we find it so difficult to discourage personal reflections and unnecessary hard hitting in some of our correspondence.-Ed. E. M.] COMMERCE AND TRADE. SIR,-1 will add a few more remarks towards the discussion of principles denied by Mr. Jardine, and to endeavour to carry readers' minds somewhat beyond the very narrow bounds to which "F. W. M." would limit them. In I think it can be best done by supposing a case. France and England there is a party protesting against the Treaty of Commerce as injurious on exactly the grounds taken by "F. W. M." although this treaty is really an approach to the coveted reciprocity; our silk manufacturers and their cotton manufacturers declare they are being ruined by the competition the Treaty has engendered, and the case I intend to suppose is, that these complaints are in both instances correct, Well the narrow view, and that which the interested persons take, is of course that this is an evil to be arrested by some limit to the competition, I now take my leave of this subject (except some The wider view is that the buyers in both cases have more forcible arguments can be brought to bear upon to be considered, and that all are benefited by obtainit), as I do not think I should be acting right by keeping what they want, and that the true remedy is for ing up this "simple" matter, when my friend the unprofitable work to be given up and exchanged "B. W. R." thinks I ought not to do so. for the other; that is to say, the French should make the silk, the English the cotton, and each exchange their surplus for what they require of that which the other can produce best. THE HARMONIOUS COTTON SPINNER. P.S.-Will "B. W. R." kindly give me his opinion on the yarn tester he mentions-the range of strengths it will indicate, and the principle on which it works? TO MILLERS. SIR, Mr. E. Davis, on page 278, in his description of silk bolters presently in use, asserts that there is not more than one-third of the silk in actual use, the rest being taken up with rails and ribs; this may be the case with some silk bolters, but certainly not all, as the firm of Thomson, Wilson, Weddell,; and Parlick, have been putting up silk bolters for the last six or seven years that have none of these cross ribs to which he refers. The rails are 21" x 2", and the whole space covered by these rails is not more than 12" in width. The circumference of the bolter is 9' 4"; deducting 12" from 9 leaves 8' 4' of silk for effective use. I have seen one of these bolters 23ft. long, dressing with ease to 6 pair of stones. AN ONLOOKER. Nothing but narrow provincialism, the idea that our own particular spot of earth is of most importance, prevents this truth from being seen and acted oa; the narrow view is only a relic of the limited "national' feeling which once made England and Scotland enemies, and at one period saw seven; distinct nations in England. The wider view is that which teaches us to regard all mankind as a common brotherhood, each nation really deriving benefit from what benefits the others, instead of the reverse, as is so commonly supposed. But F. W. M." and his kindred will say as to our supposed case that the French would like to make all silk, but will not give up their cotton making, but put the same with their silk because otherwise we must a fine upon ours to keep it up, and then we must do pay for their silk in money at a dead loss, and our supposed superseded silk manufacturer must stand idle. Now here it is that people who can see just barely as far as the tips of their noses fall into error. Nothing of the kind would really happen. This energetic and industrious Englishman would simply say to himself, "Well I shall not be quite so stupid as my French friend," he would just make his cotton and send it to India and change it for Cashmere shawls, for which the Parisian ladies would bid him a high price, and with the money paid him for these buy the silk he wanted, and probably put into his pocket a little "profit," our friend the "Harmonious Biacksmith" to the contrary notwithstanding. Of course the case supposed would never happen to any single person as here supposed, but it is what really does happen as far as the national commerce is concerned, and is just what is meant by "Herbert "and others when saying that commerce is really barter, and that taking the average of years the total imports are wholly paid for by the total exports, the higher nominal amount of the forcer being really the costs of shipment paid abroad and "profit." SIR, I believe we shall have to take what "A Stoneman" persists in saying touching,his "blindness," impracticability &c., to be perfectly true. He says that he is so blind as to be unable to conceive why the respective density of the various materials which composes a millstone should disturb its standing balance, when it becomes to run. One would imagine that enough has been said on the subject to show anyone the reason why; and to illustrate this I suggested that he should try to do so by the aid of Clark and Dunham's patent balance, which I understand he has in his stones. From such suggestion I gather that he understands me to have recommended those balances, which is not the case, though I believe with C. M. that there is no better if properly used. But to a man with his wits about him the same results can be obtained without them. For instance, if John Botting had sunk his balance box deeper, instead of transiering his shot from one boxfinto another, both balances would coincide. I would advise him to try it. The reason for so doing is that it brings the weight within the same horizontal line as the object it has to counteract, and here is the advantage of having the patent, because of its mechanical arrangement; by the aid of which "A Stoneman" says that it is improbable that a stone's standing balance can be disturbed. If he had only given the experiment a practical trial, it would have added considerably MESSRS. CUNNINGHAM & CO'S IMPROVE towards illuminating his "unenlightened intellect. He seems to think that I ignore a standing balance. Why he should I am at a loss to know. No one is more in its favour than myself, yet in point of utility, I regard it as stated in a previous letter. while it is possible by mechanical means to possess both, no one would be satisfied with one only, but this cannot be accomplished in any other way than upon the principle stated above, and the best method of driving the stone while balancing is that stated by myself in a previous number of the ENGLISH MECHANIC. As to his stones doing equally good work before he had the patent proves nothing more But Of course "F. W. M." does not look for an answer to such suppositions as those in the early part of his letter; they suppose the nation in the one case a ruined pauper, and in the other a retired gentleman living on his means; both cases quite different from that of an active business-like manufacturer and merchant, which is the actual condition of the case of England. SIGMA. MENTS IN OBTAINING MOTIVE POWER. SIR, A few weeks ago you described and illustrated in your valuable periodical an invention patented by Messrs. Cunningham, of New Oxford-street, and McCarthy, of Bloomsbury, for obtaining motive power as applicable to the propulsion of wheeled vehicles. Many inventors have laboured under the idea that a large amount of power may be stored up in spiral springs, and a vast deal of trouble and loss has been occasioned by this delusion. That invention seems to me to be thoroughly impracticable, or, as your able correspondent, Henry W. Revely, terms it nothing The more nor less than perpetual motion." But the fact of AN ENGLISH MECHANIC'S SOCIETY FOR SIR, My appeal for the establishment of this society, which you kindly inserted in your issue of the 10th inst., has resulted in some half-dozen encouraging replies. As, however, I have reason to think a number of your London readers are expecting something further to appear in your journal, permit me to say that when double the above number of hearty responses have been received, a preliminary meeting shall be convened and further steps taken. G. G. B., Ripon Lodge, Grove Park, Camberwell. CHALLENGE," P. 253. ૨ Required from these data, the two positions of A SUGAR MILLS. SIR,-There is one class of machinery which appears to have been entirely overlooked by your numerous correspondents-I refer to sugar mills for extracting the juice from the sugar canes. As this is the time time for the next sugar season, I think it would not when mills are being made to send to the colonies, in be amiss if we now had a little information about I believe the only book published on the them. strength of sugar mills is by Burgh. In it the calculations are all based on the supposition that the length of the roller is equal to twice the diameter; but this, of course, does not happen in the majority of cases in actual practice. I should like if some of your valued correspondents would give some practical rules for proportioning the different parts, holding-down bolts, roller shafts, &e.; also the pressure required to squeeze the juice out of canes of an average ripeness. Information respecting breakages would also be valuable. As many of your subscribers go out abroad with mills, I am sure they would be delighted with any facts relating to their working, &c. I am myself much interested in them, and should be pleased with any practical hints regard ing their manufacture or working. SIR,-I beg to enclose you a rough sketch of additions to a bicycle different from any that I have seen in your columns. The advantages of the addition are twofold-firstly, by the addition of the multiplying wheel A the revol ution of the driving wheel arc doubled without the necessity of moving the feet so fast as formerly; and secondly, by the crank being attached to the wheel A, instead of the wheel B, as is usually the case, the crank is brought nearer to the saddle, which will allow of the driving wheel being made much larger than it is at present; for owing to the average allowed for the length of a man's legs, the distance from the saddle to the cranks must in the present 352 SIDE THE "MILTONIAN" BICYCLE. SIR,-Enclosed I send you sketch of a very simple kind of bicycle which I invented last summer, and intended to send it to you then; but I had previously sent a sketch for a spring wheel, and it was not inserted, so that was the reason I did not send the enclosed sketch. But seeing in the last week's issue a bicycle invented by the "Phantom" Veloce and Carriage Wheel Company which was touching on the same principle as mine, I made up my mind to send it. I can claim some very good features in it :-First, the very simple way in which it is made, as any one that can make a wheel could easily make the rest, with the exception of the ironwork, which is not very much-only the crank, pedals, brake, saddle, &c. the total 4in. in place of 34in. Now Figs. 1 [and 2 Again, Mr. Baskerville says "the belief that the Now, for instance, the link being in centre of valve spindle, the rods will vibrate above and below the line of valve spindle A, thereby adjusting and keeping the centre of link as centre motion, and will do so so long as that centre is in centre of valve spindle, but if we bring the rod in contact with spindle, we make that particular rod give motion to the valve until the centre of link is brought to centre of valve spindle, and just the same with rod D, if we stand and watch a link at work, with the lever in the end notch, we shall see the centre of link vibrate; for this reason the centre of link for the time being is not the centre of motion, but the centre of motion will be found about 2in. higher up or lower down if the rod D be in contact, this is caused by what our friend terms the crossing of rods, but principally by that 'W. T." (June 17, page 304) it is very evident that the lowness of the modern pianoforte detracts from its power at least in the bass strings. Another difficulty is to find a shape of case that is at the same time saleable to the general public, and will admit of the greatest length of string. I enclose a sketch I have made bearing these two points in view, which I beg to commend to the attention of "W.T." thinking, if it does not fulfil the one condition of saleability, it would increase the value of the instrument in a musical point of view. ALEXANDRA. P.S.-Am I never to have my harmonium of the present with great variety of quality of tone, soft and loud. The harmonium of the future of your correspondent "R. T."justifies its name, and he has never enlightened me on the points inquired about issue of March 18. BOILER SAFETY VALVES. SIR. I read an elaborate account in your No. 72, written by "T. J. O'O.," on the "Safety Valve," and in your No, 273 "J. Howell" gives his theory to calcalate the pressure of the same, but in going through FIG. which is not very troublesome to make. Secondly, there is no danger of the legs coming in contact with the wheels, as they are enclosed in a box, which prevents all splashing or dust flying. You will see it seers from the centre, between the two wheels, which are kept together by a hinge joint. The saddle spring can be made of wood or steel, the front end of which would be fixed on an upright pin, so as it could turn, and the back end would be loose, to give freedom for turning. The pedals would be greatly improved if they were covered with indiarubber, which would keep the foot from slipping, and greatly lessen the jolting to the feet. Any other information I will gladly give if required. A. B. HANDFORD, West Milton, Dorset. LINK MOTION. SIR,-I am much obliged to Mr. J. Baskerville for bis able way of treating of the link motion, He shows himself however, not very exact on some points of the steam engine viz., lap lead and link motion. Now if Mr. Baskerville was well versed in link motion, he never would have said what he has, viz. : "that the whole amount of vibration must be communicated to the centre of link." This assertion I must say is not correct, inasmuch as the centre of link is never expected to transmit any motion to the valve; I do not deny that the centre of link does move when at work with the lever at either end notch, but this I do emphatically deuy, that the centre of link will vibrate when that centre is in a line with valve spindle and crank shaft, and the diametrical centres are in opposition to each other, no matter at what angles they stand with the crank, because both eccentrics should have one throw, consequently both travel one distance; and at the same speed, but in opposite directions, thereby making the link centre the centre of motion for each end. Now let me take Mr. Baskerville's supposition viz.: "1in. of lap and in. lead and multiplying by 2 gives us 34in." which he says is the proper amount,' Eut there he is wrong again; because we must have more vibration to open the valve in. more, making E B B D D G the latter, I find there is a mistake in the subtraction. The figures 419, 4910, should be 409, 4910. This throws the remaining part of the calculations wrong. But it strikes me that "Templeton's way of calculating this valve is much more simple than either of the above, and if you think it worth while to insert it in your columns, I herewith describe it. Take a light line at the centre of valve B, which is 3" from A, the point of resistance, and hook it on to a Salter's spring balance or steelyard when the valve is connected to the lever, and supposing the weight to be 35lb., this is the effective pressure against the steam at the orifice of the valve, or=5lb. per square inch, the area of valve, and then by adding the weight of a ball, 15lb., which with weight of lever and valve will equal 201b. to the square inch, and for every 3" from the point of resistance A, the pressure will be increased 201b. FALCON. READINGS FROM THE GLOBES.-V. SIR,-In illustrating geographical phenomena by the globes, it is sometimes expedient to consider the earth as staticnary, and the stars and sun as revolving round it, but this it is to be understood is done for the sake of illustration and no more, it by no means implies heresy, the party may belong to the orthodox faith, although he makes this supposition. The object in dealing with these questions is to illustrate, not to philosophise, and although astronomers have demonstrated that the sun is the centre of our solar system, and that the stars have a proper motion of their own, it particular rod that is not engaged; being 16in. below will not at all militate against their conclusions, when, the centre line of spindle, thereby receiving all the for the sake of illustration we make assertions which angles, and causing that end of link to have almost seem to contradict them. In the following remarks double the vibration, and would make the link into a we shall consider the pole star as immovable, and common lever if the 4 of vibration given out by the we shall move the globe in any direction as may best rod B which throws the centre of motion as shown at answer our purpose. If Archimedes was unable to 9 Fig. 3. Fig. 1, B1 and D1 shows eccentric rods when move the world, for want of a place on which to fix lever is in centre notch B3 D3 when at end notches; the his machine, we can at least move our miniature globe same with Fig. 2; the full lines in Fig. 3 represents to suit our convenience. The sphere may be reprethe rods when the crank is at CB, CD, and CE, respec-sented under three aspects. (1) the right sphere, (2) tively. JAMES HARRISON, Hyde, near Manchester. the parallel sphere, (3) the oblique sphere; and we shall show the appearance of the sun and stars to. those who live in each of them. These aspects of the sphere have particular reference to the pole star and the equator. Where the equator makes right angles SIR, After reading the clear statement of the dif- with the horizon, as in Fig. 1, there we have a right ficulties in piano construction by your correspondent | sphere, and in whatever sign of the Zodiac the sun is STRING SPACE IN THE PIANO. |