a I am, IN OF THE ON THE MACHINERY EMPLOYED IN THE MANUFACTURE OF GAS. $ Fig. 5, Is a side view of another wag- stirring action to the substance to be gon-tilt steam-boiler, showing another boiled as in the case of soap boiling, arrangement of pipes or tubes. The palm oil, or other oils. two external ones proceed as above de- Fig. 20, Is a view of the under side of scribed from the box A, and as shown the same boiler. in the under view, fig. 6, and pass under- Fig. 21, Is the front end of the boiler neath the bottom of the hoiler; but in. fig. 5, and section of brickwork. As the stead of passing to the opposite end, rapid action or circulation produced in they are turned sideways, and pass into the arrangements must necessarily carry the boiler at its sides above the level of off much of the heat from the furnace, the water within it. The two pipes or therefore it will be desirable to supply tubes next to them likewise proceed from it with hot air, this may be effected by the box A, but enter the back end of the dividing the brick flues passing along boiler above the level of the water, in the the sides of the boilers in the middle by manner first described ; the middle pipe means of metal plates, as is seen in fig. 2, proceeds from the box A, a certain dis- at JJ. tance underneath the bottom of the boiler, Sir, and then returns and enters the boiler Your obedient servant, at its front end above the level of the ED. WHITELEY. water. Fig. 7, is a front view of boiler sig. Langham Place, Feb. 1839. 5. Fig. 8, back view of the same. Fig. 9, transverse section through the boiler, showing the metal diagonal plate C perforated with holes. ON THE MACHINERY EMPLOYED Fig. 10, Side view of cylindrical boiler MANUFACTURE ILLUMIwith hemispheric ends with the apparatus attached. Fig. 11, back end view of Sir,-Having done me the honour to boiler fig. 10. give publicity (in No. 811 of your jourFig. 12, Elevation of the front of a nal) to a description of my hydraulic marine boiler, composed of six boilers gasometer counter-balance, I am inarranged side by siile. Fig. 13, back duced to adılress you upon the subject view of the same. Fig. 14, side view of of the manufacture of coal gas. the same. It will scarcely be credited by indivi. Fig. 15, The upper part of one of the duals not immediately engaged in the pipes or tubes B B, on a larger scale, actual production of this article, that and being formed with copper lined in- there is no other branch of our domestic side or any other metal less liable to cor- trade conducted upon less economical rosion then iron and copper alone, and principles; and it is a fact that merits fitted by means of screws, or otherwise investigation on the part of gas-proto the other part of the pipe. prietors, that an immense annual sum of Fig. 16, Upright metal pipe to be money is annually sacrificed by many of screwed on to the top of the boiler, a our large establishments in consequence valve opening upwards from a short pipe of the enormous waste of gas, and dein the tube, and also a pipe for the pur- struction to the apparatus, which contipose of conveying steam to vapour baths nually result from the defective modes and other vessels. now generally practised in the geneFig. 17, Represents an open boiler rating and storeing processes. having a pipe or tube proceeding from We frequently hear of the great imits lower part, and passing underneath provements that have been made upon the boiler through to the fire and enter- the machinery of the early gas manuing at its upper part. facturers; but it will be found upon imFig. 18, Similar boiler furnished with partial inquiry, that those improvements four similar tubes. have not effected any material diminuFig. 19, Another boiler with 3 pipes tion in the cost attending the production or tubes, which, instead of passing per- of illuminating gases; they have merely pendicularly, as in fig. 17 and 18, are gone to the extent of rendering the pricurved and pass obliquely upwards, en- mitive machinery more picturesque in tering the boiler at tangents, whereby appearance, and perhaps in some few inthey will give a circular movement or stances, more scientific in construction. a а m 6 ON THE MACHINERY EMPLOYED IN THE MANUFACTURE OF GAB. That we derive no pecuniary benefit from with the introduction of what may in reathose improvements may be ascertained lity be termed substantial inventions. But, from the knowledge (which is every day unfortunately for the prosperity of gas probecoming more extended (that the pre- prietors, there exists a species of intersent manufacturers do not produce the dict to the admission of real improvearticle at less cost than the early specu. ments; particularly when such improvelators in the trade; indeed I am convinced, ments emanate from the minds of honest upon the testimony of the most skilful artisans, whose excellent practical sugmen employed in the works of the me- gestions would (were they to obtain tropolis, that gas was produced at consi- publicity) tend to expose the destructive derably less expense 15 or 20 years ago effects to gas property, which the mathan it is now. chinery of modern theorists is now proIf this be the case, the question will ducing arise— What is the intrinsic value of If a similar system of exclusion were that progress which an experience of tolerated in other departments of manunearly a quarter of a century has ena- facture, the public would not derive the bled us to make? With respect to pecu- same amount of enjoyment from the niary advantages, gas companies assur- purchase of superior and cheap commoedly have accomplished nothing; on the dities as they do at present; neither contrary, the immense expenditure of would capitalists obtain a fair return for capital involved in the introduction of the vast sums of money annually emmerely a more elegant description of ma- barked in the production of marketable chinery has tended to lessen the profits articles; and it is to be regretted that gas which might have been derived from the proprietors are extensive sufferers from manufacture, were it conducted upon the prejudice and ignorance hourly maprinciples that are more in accordance nifested by persons who are entrusted with our present knowledge of che- with the conducting of the manufacmistry. turing process of an article, which, unWe find (notwithstanding the flatter- der more favourable auspices, might be ing but unfair eulogiums passed by in- rendered a most lucrative trade. terested parties upon modern improve- But this manufacture cannot arrive at ments in this art) that in 1820) as great, that state of perfection to which it must if not a greater, quantity of carburetted ultimately attain, until proprietors are as hydrogen was evolved from a given thoroughly initiated in the peculiarities or quantity of coal, than in 1839. The mysteries of the various processes as the quantity of fuel consumed in the retort most skilful of their operative servants. furnaces, also, is not less at the present Then, indeed, will their property become time than at that period ; and in the a source of profitable revenue; as the article of lime required for purifica- insight which a determined study of the tion, the quantity consumed immeasura- subject must secure them, will, they may bly exceeds that which was used by the be assured, enable them to detect (withearly manufacturers. out relying upon the representations of It is evident, therefore, that the im- others) much that has been extremely provements alluded to are little better detrimental to their interests. than imaginary, certainly neither perma- I shall now, Sir, with your permission, nent nor substantial advantages have proceed to the practical part of my subresulted from them: the inventors, it is ject, by laying before the numerous true, have in many cases realised for- readers of the Mechanics' Magazine who tunes, while the proprietors of gas esta- are interested in the welfare of this trade, blishments have not received any satis- a detail of the losses to which gas factory return for the capital they have property is exposed, in consequence of advanced, in order to bring into opera- the defective operation of certain portions tion the fanciful contrivances of ingenious of the apparatus. speculators. In the description of the Hydraulic During the last 25 years the machinery Counter-balance it will be observed that employed in all other branches of ma- I have attributed the damage to gas nufacture has been improved to a vast works, and waste of gas, chiefly to the extent; and the capitalists engaged therein injudicious practice of conveying the gas have derived advantages commensurate into heavy reservoirs. It would appear ON THE MACHINERY EMPLOYED IN THE MANUFACTURE OF GAS. 7 that manufacturers are not conscious of retorts; and for the remaining seven this important defect, otherwise we should months this number is reduced to about not witness in several of the Metropolitan 200. The average number of retorts in establishments the crowns of their gaso- action during the whole year will be found meters loaded with several tons' weight to be about 250. of metal, during the process of charging By calculation it will be seen that the them. This accumulated weight is re- unoccupied space in each retort (that is, quired to give an increased impetus to the space immediately over the coals) the current in the street mains; but it when added to the cubical area of the must be apparent that the same gasome- internal space of the ascension pipes, and ter thus loaded, will, during the time oc- the contents multiplied by the number cupied in charging it, cause a continuous of “ draws" that take place in twentyrecoil upon the whole of the internal ma- four hours-that a waste of gas to the chinery; for the progress of the fluid in amount of at least 8l. per week is inits passage from the retorts, must be ma- curred. terially retarded by this opposing force; But these are not the only evil effects and it is only the superior momentum that result from using weighty resercommunicated to the gas by the intense voirs ; for the products extracted from temperature of a proportionate number the coal being confined for too long a of generating vessels, that enables it to period in the generating vessels, a greater overcome this extra weight of metal. accumulation of sulphuretted ingredients In a clear sun-shiny day, the effects of mixed with oxydized iron, will attach to the “back pressure " thus created, will the interior surfaces of the retorts; hence be conspicuous in the retort house, as the troublesome and destructive pronearly the whole of the internal space of cess of “Scurfing" will more frequently this building is occupied by a (more or be required. less bulky) volume of a pale violet tinted The gas manufacture is often inconvevapour. The experienced eye of the in- nienced by the stoppages that take place telligent foreman of this department of in different parts of the pipes leading the works, will readily observe that this from the retort-house to the reservoirs ; vapour is a considerable portion of the these interruptions are caused by accucarburetted hydrogen, which the heavy mulated deposits, formed of ammoniacal gasometer is causing to issue from the salts, oxide of iron, and liquified pyrites ; fractures and interstices that are pro- the passages of the inlet and outlet pipes duced, by the same cause, in the re- are frequently impeded by these depotorts, the ascension pipes, and hydraulic sits; and the orifices of the pipes being main. I have frequently remarked the thus to a certain extent choked up, honest regret depicted upon the counte- forms an additional impediment to the nances of some of our experienced free transmission of the gas from the restokers, when viewing this irredeemable torts to the gas-holders. Effects of this waste of their unconscious employers' nature may be in a great measure avoided property. But this is merely one instance by working gas-holders of light weight; of the destructive effects resulting from as, for example, suppose that a gas“ back pressure.” I am aware that there holder is equal in weight to 12 tons, this are many individuals engaged in the weight may be reduced to half that manufacture who believe this vapour to amount by attaching to the counterbe the steam generated from the moist balance-chains light tanks, capable of luteing of the retort-lids; and while this containing six tons weight of liquid, and fallacious opinion is entertained by pro- when the gas-holder is charged to its full prietors, the waste of gas produced in complement, the liquid, by means of this way will be perpetuated. self-acting valves, may be discharged; We shall now endeavour to estimate thus the weight which was deducted is the quantity of gas destroyed during the again recovered, without resorting to the process of drawing the charges from the dangerous and inconvenient method pracretorts. tised of removing and replacing the solid During the winter season, which may weights which are at present in use in be estimated at five months, several of several of our factories. the large works employ from 300 to 400 By working gas-holders with tanks |