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at an obtuse angle; these, after being well softened by annealing, are then subjected to the action of another pair of dies, by which their rims are turned
up still more; they are then again annealed, and pressed between another pair of dies, which brings their rims into nearly a cylindrical shape ; and then, after again annealing, they are pressed by the action of other dies into a perfectly cylindrical form. The next process is, by means of a circular bed and punch, to cut out the entire flat piece of metal, and thus to leave a cylindrical ring only, like a ferrule; this is then placed, after being again well annealed, in a pair of concave dies in the screw-press, in an upright position; and the effect of the dies upon it is, to contract each end of the cylindrical ring a little inwardly; another pair of dies succeeds to these, which still more contract the ends, -and again another pair, and so on, observing to anneal them well between each operation; until, at length, a globular, or oval hollow bead is thus made, having merely small holes in its ends, which are necessary to its use. And thus, and without any joint or seam, is a regularly shaped hollow body formed out of a plate or sheet of steel !
The facets are formed upon the surfaces of the steel studs and beads, either by filing them whilst in the soft state, and in which mode the more expensive kinds are prepared, -as well, also, as others; or, after they are hardened, by grinding upon flat pewter laps, with the assistance of coarse emery and water, in which way the more numerous and cheaper kinds are cut. Their appearance will either be similar to that represented in fig. 2, which are round and oval studs, viewed in plan and edgeways;
or like those shown in fig. 3, which are holFig. 2.
low beads, having two holes in each and a Fig. 3.
wire passed through them. The filed studs and beads being case-hardened, as well, also, as those which were cut after hardening them,
are now in the state in which the marks left in them by the file, and those caused by the coarse emery, must be removed by the application of finer sifted, or washed emery, either mixed with water or oil; in the former case, by the use of hard flat brushes, continually rubbed over them backwards and forwards, when cemented upon a broad and extended flat surface; or in the latter employment of oil and emery, by holding them against cylindrical brushes, mounted upon square spindles, 'conically pointed at their ends, and turned in the lathe, either by the foot of the workman,—the longwheel, as it is termed,-or in mills, on large scale, by the powers of water or steam. When this process has been performed for a sufficient length of time, or until the coarse file or emery marks are removed, then a still finer kind of washed or flour emery must be employed, mixed with oil, and applied upon an entirely distinct brush or brushes from those used in the last operation; and this process must also be continued until the finer marks, left by the last emery employed, are likewise in their turn completely obliterated; and the articles will then be fitted to receive their ultimate black polish and lustre. Instead of mounting the beads upon cement-blocks, they may
be strung upon wires, when applying emery and oil to them; and thus save the trouble of repeatedly mounting, and again remounting them on the
cement-block, in a different position to the former ones, in order to receive the effect of the emery over their entire surfaces.
The last finish, or polishing, can only be properly given to the steel studs or beads by employing putty, or the combined oxides of lead and tin, finely ground,-and either with water, or, which is better, with a mixture of alcohol and water, or proof-spirit, applied upon the soft skin of the palms and inner sides of the fingers of the hands of women! Nothing equal to this process having hitherto been discovered in practice, to give the steel its black polish or lustre.
Having thus generally described the processes employed in the manufacture of polished steel studs and beads, we may here remark, by the way, that the very same method of soldering with brass, employed in fixing the wire stems in the studs, is likewise used by the locksmith, in soldering the delicate wards of his locks; and also by the vice-maker, who thus firmly combines the threads of the hollow screws in his vices with their surrounding boxes, and their other adjoining parts, instead of cutting them, by means of taps, out of the solid metal in the ordinary way; and yet so firmly are they thus united, that an instance of the thread of the screw stripping or quitting its place in the box, by the utmost power applied in using the vice, is a very rare occurrence, and, indeed, scarcely to be met with!
[To be continued.]
JOINT-STOCK COMPANIES OF 1835. We have extracted a list of the projects which were laid before the public in 1835, and recommended by their several patrons, as eligible means of investing capital. If the list were quite complete, it is supposed the amount of capital proposed to be raised, would equal that of the too-celebrated year of speculation, 1825. Whatever may be the fate of these schemes, it is impossible not to regard without deep interest, the enormous sum of energy, talent, skill, and money, which even the steps necessary for their mere announcement, have put into motion.
Capital. Agricultural and Commercial Bank of Ireland
£ 1,000,000 Bank of South Africa
15,000 120,000 120,000
28,000 100,000 30,000 20,000
20,000 200,000 30,000 50,000 200,000
2,500 50,000 20,000 50,000 30,000 60,000 10,000 20,000 20,000 20,000 40,000 30,000 30,000 112,500 100,000
30,000 480,000 30,000 20,000 19,200 20,000 120,000 25,000 30,000 500,000 25,000 30,000 25,000 60,000 16,000 220,000 110,000 15,000 60,000
700,000 1,244,000 400,000 600,000 500,000
140,000 1,000,000 1,500,000
Capital, Gravesend and London
600,000 Great Western
3,000,000 Grand Atlantic
3,000,000 Grand Surrey Canal and Junction
600,000 Great Northern
3,000,000 Grand Northern
4,000,000 Hull and Selby
270,000 La Loire
200,000 London Grand Junction
600,000 National Pneumatic
200,000 North Midland
1,250,000 North of England
1,000,000 Preston and Wyre
130,000 South Eastern
1,000,000 South Durham
150,000 South-West Durham Junction
50,000 Southend and Hole Haven
300,000 Tower of London
1,000,000 Thames Haven
450,000 Windsor and London
£35,424,000 MISCELLANEOUS. Anti Dry Rot Company
£250,000 Bognor Improvement Company
200,000 British Agricultural Loan Company
2,100,000 Cornwall Royal Tin Smelting Company
100,000 Deptford Pier and Improvement Company
50,000 Danube and Mayne Canal Company
833,000 Equitable Discount Society
100,000 Equitable Society
210,000 Equitable Reversionary Interest Society
300,000 Eastern Metropolitan, Surrey, Kent, and Sussex Society
150,000 Gravesend River Thames Floating Bath Company
20,000 Hastings Improvement Company
200,000 Imperial Anglo-Brazilian Canal, Road, Bridge, and Land Im
500,000 provement Company London Reversionary Interest Society
400,000 Licensed Victuallers’ Fire and Life Insurance
150,000 Mexican and South American Company
100,000 Metropolis Pure Soft Spring Water Company
300,000 National Provident Institution Norwood Park Estate
20,000 Pennsylvania Coal, Land, and Timber Company
135,000 Prospective Endowment Association
1,000,000 Patent White Lead Company
100,000 Rio De Anori Gold Stream-works Company
25,000 Shetland Fishery Association
100,000 South London Market Company
250,000 South of England Reversionary Interest Association
50,000 South Australian Company
500,000 United Investment Company
£ 8,193,000 SUMMARY. Banks
£ 1,150,000 Steam
DESCRIPTION OF MR. PERKINS NEW STEAM-BOILER.
AS COMMUNICATED BY HIMSELF.
The vast extension of the manufactures of Great Britain, and the facilities of communication, with other advantages, arising from the application of steam, cannot fail to render a description of any further improvements in that powerful agent interesting to our readers.
The following are the advantages which result from a new modification of the circulating steam patent, granted to me in 1832:
1. Absolute removal of all the danger from explosion.
5. There being no possibility of any deposit of foreign matter in the generators.
6. No furring-up of the boiler, as all the deposit will of itself collect in a place provided for it, and be blown off at will.
7. The generators always being kept at the evaporating point.
8. The impossibility of burning any part of the boiler or generators by the most intense heat.
9. The boiler and generators not being in the least injured by expansion and contraction, owing to the peculiar arrangement of the tubes or generators.
10. The perfect and simple method of separating the steam from the water and foreign matter.
11. The getting up of the steam in less than half the time hitherto required.
12. The simplicity of the construction of the boiler, and the ready means of repair.
13. The power introduced of using Anthracite coal with good effect.
The above facts can be demonstrated not only theoretically but practically. An operating model of this boiler may be seen daily at present (afterwards occasionally), at the Gallery of Practical Science, AdelaideStreet, between the hours of twelve and two.
Explanation of the first-mentioned Advantage. The great drawback upon the important invention of steam-navigation has been the disastrous effects caused by the explosion of steam-boilers. The great importance of a perfect remedy will readily be admitted. The many experiments which I have made within the last ten years, go to prove that if the steam be generated in tubular boilers, no danger can result from explosion; but there are many almost insurmountable objections to tubular boilers as hitherto constructed, particularly for steamnavigation. The boiler now about to be described, possesses apparently all the properties required. To show the reason why this boiler is free from explosions, the causes (of which there are at least three) must be described.
The first and most common cause is from the pressure of common steam. What is meant by common or pure steam, is such as has not