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by the ingenious Mr. George Heaton of practical machinists, by whose presence he Birmingham, whose persevering attempts felt himself so much honoured, for presentto apply steam power to common road ing them with certain detailed observations travelling must be fresh to the remem which from time to time he had heard Mr. brance of our readers, as is also, we
Heaton make, and in which he fully con. trust, the good sense and candour with curred. Friction, then, might be diminished which he ultimately abandoned them.
by applying proper materials in the conOur Birmingham contemporary's report
struction of axles, and the bearings on which of this lecture we subjoin.
they had to run; and by neglecting this im.
portant consideration the wear-and-tear in BIRMINGHAM PHILOSOPHICAL INSTITUTION,
machinery might be indefinitely augmented.
Nor was it enough to know, with reference Dr. Melson's Sixth Lecture on Physical to any individual article, as for instance of Mechanics.
brass, that a spindle placed upon a bearing The great interest of this lecture consisted of brass was the best practical method of in the elaborate exposition which it contain diminishing friction ; but the quality of the ed of Mr. George Heaton's views of friction brass itself was also an item of the greatest and balancing, illustrated as they were by importance. Thus, let an iron spindle, numerous models which could not fail to having two necks or journals, carrying a convey to the minds of all present the most wheel or other machinery giving a pressure decided conviction of the truth of the state. of 200 lbs. upon every square inch of bearing ments which were made, and the important surface on the journals, be made to rotate deductions derived from them. A lecture 200 times per minute, upon bearings of such of more practical value, we are convinced, brass as is used in the manufacture of pins, has seldom, if ever, been given within the (soft brass,) and to be worked ten hours walls of the institution; and the approbation a-day, the necks of this spindle will require manifested, as the lecture proceeded, by so a lubricating material to be applied three many eminent machinists as were present, times a-day, or oftener, and will, after all, could not fail to be highly gratifying to Dr. require a new brass at the end of twelve Melson, and stimulative of his valuable ex. months. If instead of the soft brass, the ertions. The inclined plane, the wedge, and hard white button brass were used, half the the screw, were first discussed, and their lubricating material would suffice, and the principles of equilibrium developed. After bearings would last twice as long. If now which, having made some preliminary ob the neck of the spindle were steeled and servations on the roughness and extent of hardened, once a day would suffice for oiling surface, the weight to be moved, the nature the journals, and the brass bearings would of bodies, velocity, and the kind of motion, last for five years ; thus not only saving so as forming important elements in the con much brass and oil, but the hard substances sideration of friction, the lecturer observed, rubbing together, having less friction, would that proper width of bearing was essential require less force to drive them. Dr. Mel. in an economical point of view, as preventive son here stated, and showed clearly, that alof that rapid decay of machinery which though the neck of a spindle running upon must otherwise occur. In corroboration of a moveable bearing upon friction wheels had this fact, an instance had been related to less friction, yet in practice these wheels him some time ago, by Mr. Heaton, of the were not so valuable as in theory they ap. wheels of a locomotive engine working on peared to be. Not only was the spindle, in a tram-way between Pontypool and New. fact, rapidly trodden away, but by the port about ten years ago.
These wheels springing of the iron or other material of were 4 feet in diameter, and only zths of an which the friction-rollers and the spindle inch in width on the face, and were made of were made, although the resistance caused cast iron. The consequence of such a nar thereby was thought to be very minute, yet, row bearing was, that the wheels would, in in practice, when these cylindrical bodies a fortnight's regular work, wear away from were pressed together by a heavy weight, the 4 feet diameter to 3 feet 7 inches, being resistance was very considerable, so much so covered on their bearing surface with small that by the continual springing of the metal loose particles of iron, in flakes siinilar in it might be shown that the spindle was, in size and thickness to the scales of small fish, point of fact, continually running up an inwhich was the general appearance wheels clined plane. Dr. Melson having shown how assumed when much trod away by friction. the wear-and-tear of friction wheels may be As it was of the greatest importance, in a experimentallyillustrated, and how necessary practical point of view, to prevent friction it was for the contrivers of machinery to as much as possible, Dr. Melson said he provide for the effects of friction, unless, inshould offer no apology to the number of deed, they would have what seemed so per
IMPERFECT BALANCING OF MACHINERY.
fect in the form of models and drawings, as turning, sawing by circular saws, ornaturn out useless in the attempt to bring them menting by the aid of rose engines, &c., the into action, proceeded to the subject of covers of snuff boxes and other fancy arBalancing. The position which he was pre ticles, that, finding his hand power insufpared to maintain at the outset of this part ficient, his lordship determined to have a of his subject was the following :—There is small steam-engine erected of sufficient not among machinists sufficient care taken power to drive the lathe, &c., at the reto construct all revolving machinery as nearly quisite speed. The engine having been put as possible in balance. This would appear up, his lordship and many of his visitors in a more striking point of view to be of were surprised to find that when one of the importance, when it was seen, as he was now lathes was urged to a speed of about 600 prepared by models to prove, that inatten revolutions in the minute it began to shake, tion to balancing diminished according to a and shook to such an extent as the speed certain function of velocity, the power; and was augmented as to raise the whole lathe originated, in the second place, so much and frame from the floor upon which it was destructive, dangerous, and at all times dis placed. Mr. Heaton was, of course, conzgreeable rocking and agitation in machinery. sulted as to the cause of this agitation, and And, first, deficient balancing produced di he attributed it unhesitatingly to the fact minution of power. Here Dr. M. described that the revolving parts of the machine, the the crank, and particularly the double crank, pulleys, were not equal in weight on both with its connecting rod-stating its use in sides of the centre. The lathe was of beauconverting an alternate rising and falling tiful workmanship, made by one of the best motion into a rotary one, as in the locomo makers in London, and the pulley suspected tive engine, and vice versa. He now took of the fault was made of rosewood, on which into his hand a model of a locomotive crank was fixed a dividing-plate. Now, it was shaft, and showed how difficult it was to probable that the texture of the wood being make it revolve above once or twice with closer on one side than on the other when the greatest force he could exert upon it by dry, was the cause of this inequality in the his fingers. This done, he took up one weight. Mr. Heaton had immediate instrucexactly similar, but having a counterpoise tions to remedy this defect if possible, and to each crank, and by the same force it per he accomplished it in the following manner : formed with ease several revolutions. The -He bored a hole on the light side of the lecturer next ran a rod of brass into the head pulley 3} inches from the centre, and introof a running capstan, and having placed the duced into it nine ounces of lead, which was brass rod so as to project equally on each the quantity required to make the pulley side of the head, caused it to revolve by perfectly in balance. The lathe was now means of a six-pound weight; it continued again set to work, and at a speed of 600 to revolve for 46 seconds, and performed in revolutions per minute, or any other speed the time 241 revolutions, as read off on a requisite for its work, it was perfectly free counter. He next put the rod all out on from shaking. This rocking motion was one side, and all other things being equal, now illustrated on a large model, whose axis the rod revolved only 30 seconds, and per was of the breadth of the ordinary railway formed only fifty revolutions. These expe gauge, and its two revolving rods of the riments proved the position that inattention length of the diameter of the wheels of a to balancing involves a decided loss of power. locomotive engine. Being unequally baExperiments were next instituted to show lanced, and made to revolve by a weight of that under these circumstances an increase six pounds, it exemplified the rocking motion of power may not only be thrown away, but of the lathe. The same motion, Dr. M. that such an increase will absolutely tend to observed, may also be noticed in some of diminish the velocity. A three-pound weight the guide pulleys that are heavy-sided on caused a model out of balance to revolve the railways, where a rope is used to draw longer and perform more revolutions than a the train along, particularly when the train six-pound weight. This brought the lec. runs fast. Here several corrections of ma. turer to his second position, viz., that do. chinery, both of lighter and more ponderous ficiency of balancing will creato a rocking construction, were severally detailed, in motion and an agitation of the machinery which Mr. Heaton had succeeded, by atwhich will be greater or less as the want tention to this principle, in producing an of balance is greater or less. It was in the equablo motion, where before the most vio. year 1810, whilst Mr. Heaton was employed lent and unaccountable agitation had preat Combe Abbey, by the late Earl of Craven, valled. One striking instance occurred in in a part of his lordship's establishment kept the latter part of last year : an application for the amusement of himself and his vist. was made to the Arm of Henton Brothers, tors in tho praction of mechanload pursults, Shadwell-street, for instruotions to rem*
the evil attendant upon the working of a fan itself from one side of the box upon which used for the purpose of creating a blast for the experiment was performed to the other. melting iron; this fan had been set to work, Next the cranks were counterpoised by weights but the steam-engine by which it was driven placed opposite each crank in its nearest was found incapable of getting it up to the wheel, and the same velocity having been required speed, which was about 1,000 revo. communicated to its revolutions, it revolved lutions per minute, and when it approached rapidly without the slightest perceptible agitathat speed it shook the whole of the build. tion. Now, to show that it was not merely ings, and shook itself loose from its bearings. the increased momentum in the revolving To obviate this position of affairs, the pro wheels which gave the model this steadiness, prietors removed it into another position, Dr. Melson removed the counterpoises, and and propped it with strong timbers, which substituted larger weights in their place, and strong timbers had their bearing under a heavy the first condition of agitation was produced wall. When again set to work it shook the even more powerfully than before. Similar, whole place as before, and made so much and equally convincing experiments were noise, that the proprietors were threatened now performed on the large model. To with a prosecution for nuisance. At this show that these pitching and rocking motions critical juncture of affairs, Messrs. Heaton, were the identical motions communicated to having been consulted, immediately took the railway trains, when running at a high vefan to pieces, and found it 2lbs. 8ozs. out of locity, and that the observations he had made balance. The evil was rectified, and the fan were loudly called for by the circumstances restored to its former position, short of the attendant upon railway accidents, Dr. Melwhole of its props, &c. The engine was son now proceeded to give an elaborate now set to work, and was found capable of series of references to the newspaper accounts driving the fan the requisite number of times, of the inquests held on the bodies of the sufthe nuisance was removed, and the fan had ferers from the accidents which occurred on never since displayed any disposition to move the Eastern Counties Railway, June, 1839, from the place where it was set.
and August, 1840 ; and on the London and important observation was made, to the effect Brighton Railway, in October, 1841. From that the outside of the wings of this fan, this evidence, it was seen that the rocking which was three feet in diameter, when run motion preceded in every instance the accining at 1,000 turns per minute, does not dent ; that it was produced by augmented travel quite twice as fast as the rim of the velocity ; that the rails were perfect before wheels of a railway train when the train is the accident; that indications of lateral running at the speed of thirty miles an hour. pressure were clear and unquestionable ; that The motion of the fan was now imitated on there is the same rocking on the Great the large model, in which experiment the Western Railway; that the opinions given weights on the outside of the steel rods were by the different engineers fell short of the not propelled at the rate of fifteen miles an explication of the cause of the accident; and hour, although the effect was so violent ; that many were, in short, opinions of little whilst, at the same time, the weights travelled or no value; that there is a great difficulty, at a uniform speed in each part of their re after all, in getting at the truth in these volution. This was not the case with the cases; and that one of the witnesses, in one wheels of a railway train ; for if a train case absolutely saw the engine leap up, and were travelling at the rate of thirty miles alight off the rails. The report of the offi. per hour, the top part of the wheels would, cers of the railway department for 1842 was of course, have a much greater motion than next as carefully examined, and it was found the centre. If, then, such an effect were that the sentiments of Brunel, Professor produced by the model, when only twelve Barlow, and Sir F. Smith, as therein emounces out of balance, and only moving that bodied, went to confirm the evidence given twelve ounces at the rate of fifteen miles per at the several inquests, and to prove that the hour, what effects were we not prepared to causes were yet doubtful which originated expect from a railway wheel thrown forward the oscillatory and pitching motions that at four times the speed, and where, as in preceded the accidents. The pages of the many instances was the case, the wheels report particularly referred to were, 70, 71, were each four times that much out of bal 72, 76, 145, 194, 195, 203, &c. Immedi.
Dr. Melson now exhibited a model ately after the occurrence of the accident on of the locomotive crank shaft and wheels, the London and Brighton Railway, Mr. one inch to the foot, and made it revolve ; Heaton addressed to the Times the following when the revolution of the wheels became letter, which, however, was never printed, rapid, it shook the board upon which it was and which has never yet been before the placed with comparative violence, and rocked public.
IMPERFECT BALANCING OP MACHINERY,
Railway Accidents. "The Rocking and Jumping of Locomotive
“ Engines. * To the Editor of the Times. “Sir,-Seeing in your valuable publication accounts of various accidents on the railways, I find in several instances the accident has been attributed to the engine having acquired a rocking and jumping motion, and, in consequence, running off the rails. To prevent this, some of your correspondents advise the use of six-wheeled engines ; such being by them considered safer (but in this I do not agree) than the four-wheeled engines, and not so liable to the rocking and jumping motion. I think the cause of the complaint exists in some of each sort, and as much in six-wheeled en. gines as in four-wheeled ones; and that cause being the unevenness in weight of some portions of the machinery-(I mean the crank shaft and appendages ;) and considering that any arrangement of machinery that would secure steadiness of motion, and render accidents less frequent, would be of public utility, is my apology for troubling you with this communication.
“In the year 1831, myself and brothers constructed a locomotive engine for the common road. We found, in our first experiment, when we run the engines, (which were of 12 inch stroke only,) at from 160 to 180 strokes per minute, (which, by the arrangement of our machinery we were enabled to do,) the jumping and rocking motion was so great as to preclude the possibility of keeping our seat upon the engine ; being aware that this motion could only be produced by some portions of our machinery being out of balance, we placed a compensating weight opposite each crank, and repeated our former experiment upon the same road, and found we attained greater speed with no greater consumption of fuel; and the machine travelled perfectly steady at any speed, and free from any symptoms of rocking or shaking. Knowing that this same evil existed in locomotive engines on railways, I constructed, in the summer of 1838, a model of a crank-shaft and wheels of a locomotive engine, (to a scale of 1 inch to the foot,) and in the month of October, in the same year, I delivered it into the possession of the then resident engineer of the London and Birmingham Railway, at Birmingham; a description of which was published in the Mechanics' Magazine of April, 1839, of which the following is a copy :"Lateral and Oscillating Motion of Loco
motive Engines. Sir,--My attention having been drawn to the lateral and shaking motion of engines upon rail. ways, and believiug it to be in proportion to the
weight of the cranks and gearing, and the position in which the outside cranks, if any, are placed, I made a small model of the engine-crank shaft, with two wheels upon it, in the proportion of 1 inch to the foot, which I placed upon iwo strong upright wires, the wires having been made fast in a piece of board. I attached a weight to a string wrapped round the middle of the crank shaft, for the purpose of giving a certain degree of velocity to the crank and wheels, by falling a certain distance, and then being released, say from the table to the floor. The momentum or speed thus attained was sufficient to keep the crank shaft and wheels in motion seventy-five seconds, and the swing of the cranks produced a lateral and oscillating motion sufficient to cause the model to move, or jump across the table upon which it was placed. I then placed a weight on each wheel sufficient to balance the crank, and with the same weight to give motion, and travelling the same distance as in the first case, gave sufficient momentum to keep the crankshaft and wheels, although heavier than before, ninety seconds, and the model stood steady where it was placed upon the table.
“I submitted my experiments to the engineers of the London and Birmingham Railway, who, in. structed by the directors, ordered one of the company's engines, (the Brockhall, at that time under repair at Mr. Middleton's, the Vulcan Iron Foundry, Birmingham) to have balance weights applied to it, according to my plans, and under my superintendence. The engine, when set to work with balance weights upon the wheels* had one uniform steady pull at its work; the side sway was gone; it ran equally steady, whether it made 6 or 160 strokes per minute, which is not the case with railway engines generally, for the greater the speed, the greater the snatching and swinging motion. After the engine had worked seven weeks, and had acquired the reputation of a very steady engine, I, with the consent of the engineers of the railway, removed the balance weights from the wheels, and found the same snatching and swinging inotion with this engine as is common to all locomotive engines of the usual construction. I found that the engine, when running at or upwards of twenty-two miles per hour, would advance and recede from and to the tender from three-quarters of an inch to an inch every stroke of the engine, and proved the advantage of the balance on the engine equal to the effect on the model. Persons acquainted with railway locomotives will, from the foregoing statements, reailily see the great and many advantages to be derived from so simple and yet so effective an arrangement.-Yours, respectfully,
. GEORGE HEATON. • Shadwell-street Mills, Birmingham.'
" Since that time, some of the most celebrated manufacturers of locomotive engines have added to their engines balance weights, fixed in the wheels in so neat a manner as scarcely to be noticed, particularly by persons not much acquainted with this description of machinery. Whether the engine which caused the accident on the Brighton Railway, or the one that made the rails into the form of a snake on the Eastern Counties Railway some time ago, had balance weights or not, I do not know, but from the description of the accidents, as given in your publication at the time, I should say they had not. Why locomotive engines should continue to be made, and used, (and I know
" • Weighing one hundred and eighty-four pounds, fixed 22 inches from the centre."
they are,) without paying particular atten. possible with a heavy train,) the engine vill, tion to this subject, is a matter of surprise in spite of all other efforts to prevent 1, to me, when the cost of the necessary ap- jump off the rails. pendages to balance the cranks, connecting “ Yours respectfully, rods, &c., would not, in the manufacture of
“ GEORGE HEatox. a new engine, exceed forty shillings. Why "Shadwell-street Mills, Birmingham, this important feature in mechanics should
October 23, 1841." be neglected by railway engineers is asto Dr. Melson concluded by referring to the nishing, as it must be known to them that fact that the compensation principle was al. it is particularly attended to in all other ready beginning to gain much upon public kinds of machinery; and even by them favour; that on the Birmingham and Man. selves, when turning these same cranks for chester (Crewe) Line such engines were uni. the locomotive engines in the lathe, at their versally adopted, and that on several of the manufactory, a balanced weight is used to lines there were individual engines of this make them run steady during the operation. character. The straight-axled engine is de. To further illustrate the necessity of great cidedly superior to the other, but here the care in this department of the science of evil obtains, inasmuch as the crank-pins and mechanics, I will instance the simple ma connecting rods are not compensated. chine used for the purpose of grinding the points of pins : this is composed of two discs or pieces of steel, about 6 inches diameter, and weighing about 12 pounds each ;
NEW STEAM FRIGATE-THE LARGEST IN they are fixed upon a thin spindle or shaft, and require to be propelled round at about 3,500 times per minute. These mills or
The Admiralty have given instructions discs are always set out of truth with each
for the building and equipment of a new other, but require to balance each other so
steam frigate, which is to surpass, in size nicely, to determine their resting steady in and power, every thing of the kind yet their journals, that one-twentieth part of an
afloat. She is to be of 650 horses power; ounce out of balance with each other would to have engine room for 600 tons of fuel; render the machine unsafe to the workman, complete stowage under hatches for one being liable to jump from its bearings, and thousand troops, with four months' stores unfit for use. The outside of the discs (or and provisions, exclusive of a crew of
mills,' as they are called by the workmen) about four hundred and fifty men ; and travel but little more if so much at times) is to be armed with twenty guns of the than double the speed of the locomotive en
heaviest calibre, besides carronades. The gines-say 5,250 feet per minute, or nearly
Cyclops, Gorgon, Geyser, and other war sixty miles per hour. The cranks of loco.
steamers now talked of as wonders for motive engines (with wheels of 5 feet diameter, and stroke of piston 18 inches) travel,
magnitude, will sink into insignificance when conveying a mail train, at about one
as compared with this ; the largest of sixth, and sometimes at about one-fifth, of
them will be little more than half her the speed of the outside of the pin mill, and
size. For the sake of greater expedition are about (including the connecting rods,
she is to be made out of one of the large brasses, cutters, &c.) one hundred and eighty class frigates lately built (the Penelope, pounds out of balance, and, when the train cut into two, with 55 feet in length 44) is going at the rate of thirty miles per hour, added. The originator of this plan is has to swing round from 180 to 200 times John Edye, Esq., the able assistant surper minute : these cranks being at right veyor of the Navy, (well known to angles, and some distance from the axis of all naval architects for his invaluable the engine, one on one side and the other on
work on the “Equipment, Displacement, the contrary side of the axis, swinging round
dic., of Ships, and Vessels of War") and at such a paco, is, in my opinion, the cause of the rocking motion. The engine running yard, under his immediate superiotend
she is to be completed at Chatham Dockfor some time at one uniform speed, and at a high velocity, tho springs are acted upon
onoo and direotion. The engines are to by the unovennons or swinging of the oranks,
be on the Gorgon plan, and the comminion connecting rods, &0., until the springs and
for building theni has been given to the cranks keep tlmo with each other, when the Inventor of that plan, Mesarı. John and Jumping motion commences, and at every
Samuel Seaward. The vessel is expected stroke of the engine to Increased to a great to be fully completed, and ready for nes extent, and if the speed cannot be imme. before the close of the present year. diately seriously alterod, (whloh lo found Im. The oondust of the Government in