Read Ebook: Scientific American Supplement No. 481 March 21 1885 by Various

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No doubt many of you have been troubled with the twisting of some special light casting, and will, perhaps, spend hours in the risky operation of bending an iron pattern so as to get a straight casting. A ladleful of lead and tin, melted in a small gas-furnace, will, in a few minutes, give you a pattern which you can bend and adjust to any required shape. It enables you to make trials to any extent, and get castings with the utmost precision. There is also this advantage, that a soft metal pattern can be cut about and experimented with in a way which no other material admits of. Awkward patterns commence with us with plaster, wax, sheets of wet blotting paper pasted together on a shape or wood; but they almost invariably make their appearance in the foundry after being converted into soft metal by the aid of a gas-furnace. I refer, of course, to thin, awkward, and generally difficult castings, which, under ordinary treatment, are either turned out badly or require a great amount of fitting. As an illustration of the use of this system of pattern-making, I have here two castings of my own, from patterns which, under the ordinary engineer's system, would be excessively costly and difficult to make as well as these are made. The surface is a mass of intricate pattern work and perforations. To produce the flat original, as you see it, a small piece of the pattern is first cut, and from this a number of tin castings are made and soldered together. From this pattern, reproduced in iron for the sake of permanence, is cast the flat center plate you see. To produce the curved pattern I show you, nothing more is necessary than to bend the tin pattern on a block of the right shape, and we now get a pattern which would puzzle a good many pattern-makers of the old style.

I will now show you by a practical utilization of the well known flameless combustion, how to light a coke furnace without either paper or wood, and without disturbing the fuel, by the use of a blowpipe which for the first minute is allowed to work in the ordinary way with a flame to ignite the coke. I then pinch the gas tube to extinguish the flame, allow the gas to pass as before, and so blow a mixture of unburnt air and gas into the fuel. The enormous heat generated by the combustion of the mixture in contact with the solid fuel will be appreciable to you all, and if this blast of mixed air and gas is continued, there is hardly any limit to the temperatures which can be obtained in a furnace. I shall be able to show you the difference in temperature obtained in a furnace by an ordinary air blast, by a blowpipe flame directed into the furnace, and by the same mixture of gas and air which I use in the blowpipe being blown in and burnt in contact with the ignited coke. In each case the air blast, both in quantity and pressure, is absolutely the same; but the roar and the intense, blinding glare produced by blowing the unburnt mixture into the furnace is unmistakable. The heat obtained in the coke furnace I am using, in less than ten minutes, is greater than any known crucible would stand. I am informed that this system of air and gas or air and petroleum vapor blast, first discovered and published by myself in a work on metallurgy issued in 1881, is now becoming largely used for commercial purposes on the Continent, not only on account of the enormous increase in the heat, and the consequent work got out of any specified furnace, but also because the coke or solid fuel used stands much longer, and the dropping, which is so great a nuisance in crucible furnaces, is almost entirely prevented; in fact, once the furnace is started, no solid fuel is necessary, and the coke as it burns away can be replaced with lumps of broken ganister or any infusible material. Few, if any, samples of firebrick will stand the heat of this blast, if the system is fully utilized. You will find it a matter of little difficulty, with this system of using gas, to melt a crucible of cast iron in an ordinary bed-room fire grate if the front bars are covered with sheet iron, with a hole three inches in diameter, to admit the combined gas and air blast. The only care needed is to see that you do not melt down the firebars during the process. I will also show you how, on an ordinary table, with a small pan of broken coke and the same blowpipe, used in the way already described, you can get a good welding heat in a few minutes, starting all cold. In this case the blowpipe is simply fixed with the nozzle six inches above the coke, and the flame directed downward. As soon as the coke shows red, the gas pipe is pinched so as to blow the flame out, and the mixture of gas and air is blown from above into the coke as before. With this and a little practice, you can get a weld on a 7/8 inch round bar in 10 minutes.

There is one use of gas which has already proved an immense service to those who, in the strictest sense, live by their wits. In a small private workshop, with the assistance of gas furnaces, blowpipes, and other gas heating appliances, it is a very easy matter to carry out important experiments privately on a practical scale. A man with an idea can readily carry out his idea without skilled assistance, and without it ever making its appearance in the works until it is an accomplished fact. How many of you have been blocked in important experiments by the tacit resistance of an old fashioned good workman, who cannot or will not see what you are driving at, and who persists in saying that what you want is not possible? The application of gas will often enable you to go over his head, and do what, if the workman had his own way, would be an impossibility. When a man is unable or unwilling to see a way out of a difficulty, a master or foreman has the power to take the law in his own hands; and when a workman has been met with this kind of a reply once or twice, he usually gives way, and does not in future attempt to dictate and teach his master his own business. In carrying out this matter, it is not necessary that a specimen of fine workmanship shall be produced. A man usually appreciates the wits which have produced what he has considered impossible. In purely experimental work I think I may fairly state that the use of gas as a fuel in the private workshop and laboratory has done incalculable service in the improvement of processes and trades, and has played an important part in insuring the success and fortunes of many hundreds of experimenters, who have brought their labors to a successful issue in cases where, in its absence, neither time nor patience would have been available. I need only to call to your mind the number of new alloys which, for almost endless different purposes, have come into use during the last eight or ten years. I think the use of small gas furnaces in private workshops and laboratories may fairly be said to have enabled the experiments on most, if not all, of these alloys to be carried out to a successful issue.

I have been asked to say something regarding gas engines. The only thing I can say is that I know very little about them. In my own works we have about 300,000 cubic feet of space, all of which requires to be heated, more or less, during the greater part of the year. For this purpose we must have a steam boiler, and having this steam, it costs little to run it first through the engine, and so obtain our power for a good part of the year practically without any cost. It would not pay, under any circumstances, to have two separate sources of power for summer and winter; and therefore the use of gas for power has never been considered.

For irregular work and comparatively small powers, gas-engines have special and great advantages; and in this respect they may, perhaps, class with gas melting furnaces. If I wanted 1, or 10, or 20 lb. of melted metal, I could melt and make the casting in less time and with less cost than would be required to light a coke fire. There is no possible comparison in the two, as to convenience and economy; but if I wanted to melt 3 or 4 cwt. or 3 or 4 tons every day, I should not dream of using gas for the purpose, as the extra cost of gas in such a case would not be compensated by the saving in time. In commercial matters we must always consider first what is the most profitable way of going about our work; and, so far as I myself am concerned, I have always found it advantageous to expend some money annually on proving this by direct experiment. It is almost always possible to learn something, even from a failure.

I will now, with a blowpipe and small foot blower, heat a short length of locomotive boiler tube to a brazing heat on the table; and, in conclusion, will convert the table into a small foundry. I cannot cast you a flywheel for a factory engine; so will try at something smaller, and will reproduce a medallion portrait of Her Majesty, in cast iron, the original of which is silver, commonly valued at half a crown. From the time I light the furnace until I turn you out the finished casting I shall perhaps keep you eight or nine minutes. I can remember in the good old times 25 years ago, before I used gas furnaces, that it sometimes took about two hours to get a good wind furnace into condition to put the crucible in. My time in those days was not worth much; but if I valued it at 2s. 6d. per week, it would even then have been cheaper to use gas to do the same thing, irrespective of the cost of coke.

The age of gaseous fuel is commencing; and I feel daily, from the correspondence I receive, that there is a growing impression that gas is going to perform miracles. We do not need to go mad about it; and my own precept and practice is to employ gas only where its use shows a profit, either in time or money. Many of those present know that I am as ready to totally condemn gaseous fuel where it does not pay as to advise its use where some advantage is to be gained. You will understand that my remarks apply to coal gas only. As to producer or furnace gases, I know practically nothing, except that sometimes it pays better to burn your candle as a candle than make it into gas, and burn it as a gas afterward. The use of producer gas no doubt pays on a large scale; and things on a large scale, so far as gas is concerned, are not matters with which I have time to concern myself. The commercial use of coal gas has yet to be developed. It is in its infancy; and there are very few, if any, who have any conception of its endless uses, both for domestic and manufacturing purposes. The more general the information which can be given about its uses, the sooner it will find its own level, and the sooner the gas companies will appreciate the fact that their best customers are to be found among those who can use coal gas as a fuel for special work in manufacturing industries because it is profitable to use, and saves expensive labor. My own experiments with alloys of the rarer metals, which have not been concluded without profit to myself, would certainly never have been undertaken except with the use of gas furnaces, which were both practically unlimited in power and admitted of the most absolute precision in use; and I may safely say, without violating any confidence, that many of the precious stories and so-called "natural" products make their appearance in the world first in a crucible in a gas furnace.

At the conclusion of my lecture before the Institute at Leeds, on "Combustion and the Utilization of Waste Heat," Mr. Kitson, the Chairman, remarked that if he were a dreamer of dreams, he might look forward to the time when he would be growing cucumbers with the waste heat of his iron furnaces. Many wilder dreams than this have come true in the science of engineering; and the realization has brought honor and fortune to the dreamers, as you must all know. The history of engineering is full of the realization of "dreams," which have been denounced as absurdities by some of the best living authorities.

THE GAS METER

The instrument, as usually constructed, is shown in Figs. 2 and 3.

The counter consists of toothed wheels and pinions so arranged that if the first wheel makes one complete revolution corresponding to a discharge of 1,000 liters, the following wheel, which indicates cubic meters, shall advance one division, and that if this second wheel makes one complete revolution marked 10 cubic meters, the third, which indicates tenths, shall advance one division, and so on. Hands fixed to the axles of the wheels, and movable over dials, permit the volume of gas to be read that has traversed the counter.

DOBSON AND BARLOW'S IMPROVEMENTS IN HEILMANN'S COMBERS.

The motion for working the top detaching, the leather, or the piecing roller, as it is variously called, has also been improved. The ends of this roller are always carried on the top of two levers that are oscillated by a connecting rod attached to their bottom ends. In the new motion the connecting rod is dispensed with, and one joint saved. The joint that remains is at the foot of the levers that carry the leather roller. This joint is constructed so that it may be easily altered, and by its means one of the most delicate settings of the combing machine, viz., that of the leather roller, may be made with greater readiness than with the old system. Further, from the mode of mounting these rollers another advantage is gained in the facility of setting them. In setting with the old arrangement, only one end of the roller is adjusted at a time; in the new, the adjustment sets the ends of two rollers. With regard to the leather roller also, it was found that as the round brass tubes in which its ends revolved had very little wearing surface, they got worn into flats on the outside, and thus worked inaccurately. In the machine under notice this defect is remedied. The tubes are made square on the outside, and having ample bearing surface they keep their adjustment perfectly.

THE MUNICIPAL SCHOOL FOR INSTRUCTION IN WATCH-MAKING, AT GENEVA.

When, in 1587, Charles Cusin, of Autun, settled at Geneva and introduced the manufacture of watches there, he had no idea of the extraordinary development that this new industry was to assume. At the end of the seventeenth century this city already contained a hundred master watch makers and eighty master jewelers, and the products of her manufactures soon became known and appreciated by the whole world.

The French revolution arrested this impetus, but the entrance of the Canton of Geneva into the Confederation in 1814, rendered commerce, the arts, and the industries somewhat active, and watch-making soon saw a new era of prosperity dawning.

On the 13th of Feb., 1824, at the instigation of a few devoted citizens, the industrial section of the Society of Arts adopted the resolution to form a watch-making school, which, having been created by private initiative, was only sustained through considerable sacrifices.

In 1840 the school was transferred to the granary building belonging to the city. In 1842, when it contained about fifty pupils, it was made over to the administrative council of the city by the committee of the Society of Arts. From 1824 to 1842 the school had given instruction to about two hundred pupils. From 1843 to 1879 it was frequented by nearly eight hundred pupils, two-thirds of whom were Genevans, and the other third Swiss of other cantons and foreigners.

The school, then, has furnished the watch-making industry with the respectable number of a thousand workmen, among whom large numbers have been, or are yet, distinguished artists.

The rooms of the granary, where the school remained for nearly forty years, became inadequate, despite the successive additions that had been made to them, and it became necessary to completely transform them. The magnificent legacy that the city owes to the munificence of the Duke of Brunswick was partly employed in the reorganization, and the school is now located in a vast building designed to answer the requirements of instruction. This structure, which is located in Necker Street, presents an imposing and severe aspect. The main building embraces most of the workshops, the office, the library, and the classroom for instruction in mechanics, all of which receive a direct light. At right angles with the main building are two wings. The one to the north contains in its three upper stories workshops occupied by classes in escapements, bezil setting, compensating balances, and ruby working. On the ground floor are installed juvenile schools.

The south wing contains halls for lectures on theory, and two workshops looking toward the north. The ground floor is used for the same purpose as that of the north wing.

Finally, in the center of the main building is a wing parallel with its two mates. It is in this that is located the vast staircase that leads to spacious landings at which ends on every story a large corridor common to all the halls and workshops. It is in this part of the building that we find the amphitheater of physics and chemistry and the laboratories. Here also is located the museum in course of formation , and the amphitheater designed for certain public lecture courses.

In the way of heating and lighting all parts of the building nothing has been neglected, and special care has been taken to have the ventilation perfect.

At present the instruction comprises a practical and a theoretical course.

In general, the time taken by an apprentice to manufacture his tools is from two to three months, and he can scarcely go to work on the movements before this.

In this class the regular pupils have to execute seven pieces of work in the rough, two for horizontal escapements with key and regulating wheel, and five for various other escapements. Among these there is one for simple repetition and one for minute piece. Aside from the work fixed by the programme, the pupils may manufacture all the other complicated pieces upon obtaining the authority for it from their masters and the director.

The average time employed in performing the work imposed by the programme necessarily depends upon the capacity of the pupil, but we may say that in general ten months are necessary.

In this work, as in the preceding, he must take all his pieces from the crude metal, and he must do the forging himself, as well as the roughing down, the turning, filing, and shaping, and finally the finishing, without the aid of any other machine than the dividing one.

In general, after eighteen months of work, the apprentice goes to the finishing shop, where the delicate and minute work begins, pivoting, putting the wheels in place, and practical study of gearings. After learning how to divide a wheel correctly, he is set to work on pinions and wheels in the rough, which he must rivet, finish, and pivot according to the different planes of the pieces that have been calculated and executed by him under the direction of the master.

The programme to be followed by the pupils of the class in finishing is, as regards number of pieces, the same as that of the preceding classes, that is to say, seven.

In general, the pupil passes from the class in finishing to the class in dial-trains, where he makes two of these for his pieces--one a simple and the other a minute train. The teaching of this part is very important as regards the manufacture of escapements. In constructing the dial train, the pupil perfects his filing and learns to make the adjustments correct.

The last class in the elementary instruction is the one in escapements , the programme of which includes several distinct parts: The tools that are strictly necessary; escapement and cylinder adjustment; making the compensating balances for the pupil's pieces; pivoting, putting in place, and finishing the escapements in regulating pieces. Here, as in the preceding classes, the pupils must do all the work themselves. During their stay in the elementary classes the work done is submitted to the director, who examines it and sends it back to the instructors accompanied with a bulletin containing his estimate as to its value, and his observations if there is occasion to make any.

MACHINE FOR POLISHING BOOTS AND SHOES.

The principle of an apparatus for blackening boots and shoes dates back to 1838, the epoch at which a machine of this kind was put into use at the Polytechnic School. Since then it seems that not many applications have been made of it, notwithstanding the services that a machine of this kind is capable of rendering in barracks, lyceums, hotels, etc. Mr. Audoye, an inventor, has recently taken up the question again, and has proposed to The Soci?t? d'Encouragement a model that gives a practical solution of it. The use of this will allow a notable saving in time and trouble to be effected.

This brush revolves around a horizontal axle supported by a cast iron frame similar to that of a sewing machine. Motion is communicated to it by a double pedal, which actuates a connecting rod and a system of pulleys. The external surface of the brush contains three channels in which the foot gear to be polished is successively placed. In the first of these the dust and mud are removed, in the second the blacking is spread on, and in the third the final polish is obtained.

PERSONAL SAFETY WITH THE ELECTRIC CURRENTS.

The electromotive force and resistance is constant if the velocity is constant. The electromotive force is independent of the velocity, but diminishes as the moisture increases, and is about equal to 52,000 Daniell cells. The resistance when making 120 revolutions per minute is 2,810 million ohms. At 450 per minute, 646 million.

Yours, Respectfully,

E. ELLSWORTH.

Portland, Me., March 5, 1885.

A VISIT TO CANADA AND THE UNITED STATES IN THE YEAR 1884.

I do not know what the sensations of a man can be who is about to undergo the painful operation of execution; but I am inclined to think his sensations must be somewhat similar to those of a lecturer, brimful of notes, who has to wait until the clock strikes before he is allowed to address his audience.

The President has been kind enough to refer to the paper I propose to give you, as "Electricity in America in the year 1884;" but I would rather, after having thought more about it, that it be called "A Visit to Canada and the United States in the year 1884."

It will be in the recollection of a good many who are present that in the year 1877 I visited America, in conjunction with Mr. H.C. Fischer, the Controller of our Central Telegraph Station, to officially inspect and report upon the telegraph arrangements of that country; and on the 9th February, 1878, I had the pleasure of communicating to the members of this Society my experiences of that visit.

During the present year my visit was not an official one; I went for a holiday, and specially to accompany the members of the British Association, who, for the first time in the history of that association, held a meeting outside the limits of the United Kingdom.

We sailed from Liverpool in a splendid steamship called the Parisian. There were nearly 200 B.A. members on board; and notwithstanding the fact that rude Boreas tried all he could to prevent us from reaching the other side of the Atlantic; notwithstanding the fact that the Atlantic expressed its anger in the most unmistakable terms at our audacity in turning from our native shore; notwithstanding the fact that Greenland's icy mountains blew chilly blasts upon us, and made us call out all the warm things we possessed--I say notwithstanding all this, we reached the Gulf of St. Lawrence in safety, and I do not think that a merrier or a happier crew ever crossed the Atlantic.

There is one very interesting fact that is not generally known, and I certainly was unaware of it before I started, in connection with this particular route across the Atlantic, and that is, that by it the ship passes within only 200 miles of Greenland. The great circle that directs the shortest route from the north of Ireland to the Straits of Belle Isle passes within the cold region, and hence, while you were all sweltering in heat in London, we were compelled to bring out our ulsters and all our warm garments, to enable us to cross with any degree of comfort. The advantage of this particular route is supposed to be the fact that only five days are spent upon the ocean, and the remainder of the voyage is occupied in the calms and comforts of the Gulf and River St. Lawrence. But I am inclined to think that the roughness of the ocean and the coolness of the weather at all seasons are quite sufficient to prevent anybody from repeating our experience.

We arrived at Montreal in time to attend the opening meeting of the British Association; and at Montreal we were received with great hospitality, great attention, and great kindness from all our brethren in Canada, and we held there certainly a very successful and very pleasant gathering. There were 1,773 members of the British Association altogether present, and of that number there were 600 who had crossed the Atlantic; the remainder being made up of Canadians, and by at least 200 Americans, including all the most distinguished professors who adorn the rolls of science in the United States. As is invariably the rule in these British Association meetings, we had not only papers to enlighten us, but entertainments to cheer us; and excursions were arranged in every direction, to enable us to become acquainted with the beauties and peculiarities of the American continent. Some members went to Quebec, some to Ottawa, others to the Lakes, others to Toronto, many went to Niagara; and altogether the arrangements made for our comfort and pleasure were such, that I have not heard one single soul who attended this meeting at Montreal express the slightest regret that he crossed the Atlantic.

The meeting at Montreal certainly cannot be called an electricians' meeting. The gathering of the British Association has often been distinguished by the first appearance of some new instrument or the divulgence of some new scientific secret; but there was nothing of any special interest brought forward on this occasion. The only real novelty or striking fact that I can recall as having taken place was a remarkable discussion that originated by Professor Oliver Lodge, upon the "Seat of the Electromotive Force in a Voltaic Cell."

This was an experiment on the part of the British Association. Discussions, as a rule, have not been the case at our meetings. Papers have been read and papers have been discussed; but on this occasion three or four subjects were named as fit for discussion, and distinguished professors were selected to open the discussion.

On this particular subject, Professor Oliver Lodge opened the discussion, and he did so in an original, an efficient, and in a chirpy kind of manner that took by storm not only the professors who knew him, but those who did not know him; and I am bound to say that I do not think we could possibly better spend an evening during the coming session, or more profitably, than by asking Professor Oliver Lodge to bring the subject before this Society, so as to allow us on this side of the water to discuss the same subject.

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