Just as we have the stratum Fe, Co, Ni, Cu, with drop of valency from Fe to Cu, and insolubility in the monad salts of copper, so have we a marked drop from Os to Pt and Au, with insolubility of the lowest valency salts the fluoride, chloride, bromide, and iodide of divalent platinum. The Ru stratum shows the same drop in valency especially if we consider Ag as the last member. It does not show the array of haloids as the Os stratum, but they are more stable. It should be noted that the haloids of Fe, Ru, and Os, are more prone to hydrolysis than those of Ni, Pd, or Pt. thus showing greater preference for oxygen than the last over chlorine. It should be noted that valency mounts greatly as we descend the group the lowest three members showing themselves as tetrad, hexad, and even octad in osmium salts. It may be that the formulæ of the lower valency salts is not so simple as here shown, but that the metal nickel, palladium, or platinum forms a ring in its compounds like carbon. Like carbon they are not eager to unfold themselves to take on new associates. THE PROBLEM OF CORROSION. Among the exceedingly interesting items which are to be dealt with at the Congress of Chemists and the forty fifth Annual Meeting of the Society of Chemical Industry to be held in London in July, a session of outstanding interest will be that on Tuesday July 20, when a symposium is to be held, dealing with the subject of "Corrosion." In view of the fact that this symposium is a joint meeting of the British Chemical Plant Manufacturers' Association, the Institute of Metals, the Institution of Chemical Engineers, and the Chemical Engineering Group, it cannot fail to be of vital interest to the chemical industries. The costly effects of corrosion in every branch of engineering, and especially in chemical and gas works, are known to every constructional engineer and works manager, and if the chemist and metallurgist, between them, can remove them, they will be conferring a lasting benefit on British Industry. What British research has already don and is still attempting to do will be ex plained by a group of recognised authori ties, including Mr. Ulick R. Evans, who will deal with "The Fundamental Prin ciples of Corrosion," Mr. P. Parrish, who will speak on "Corrosion and Erosion,' and Dr. W. H. Hatfield and Messrs. T. G Elliott and G. B. Willey, who will discuss "Chemically Resistant Steels." It will be obvious that the problem is being attacked by men of considerable experience in the subjects involved, and this symposium wil be of outstanding interest to chemists. chemical engineers and the industry generally. Possibly in no branch of metallurgy has there been such great advancement, both during and since the war years, as in con nection with the production of chemica resistant steels and acid resisting irons. The introduction of novel methods of manu facture and the alloy of some of the newer and less common metals with iron and stee have produced alloys of a chemical resist (Continued on Page 40) Prominent Engineering Industries. CASK MAKING MACHINERY FOR ALL PURPOSES Messrs. A. RANSOME & CO., Ltd., Newark-on-Trent and London. HYDRAULIC STAVE PRESS. This machine is used for bending staves for wine or other casks into the form requred when made up into the barrel. The presses are worked from a hydraulic accumulator, which is supplied with water at a high pressure from a strong three-throw hydraulic pump. When a charge of staves is placed in the Press, the table is caused to rise by opening the cock communicating with the accumulator, and when the staves have been pressed into the required shape, the cock is shut, and the staves are allowed to cool in the Press, when they will have received a permanent set. The Presses can be made for belt-drive as well as hydraulic power. firms at home and abroad. Among them may be mentioned the British Dyestuffs Corporation, Messrs. Brunner Mond and Co., Ltd., Chance and Hunt, Itd. (Oldbury), Castner Kellner Alkali Co., Ltd., Runcorn and elsewhere, Electro Bleach and By-Products, Ltd., Middlewich, Orr's Zinc White, Ltd., Widnes, The United Alkali Co., Ltd., Liverpool, etc., and numerous breweries, paint, white lead and cement, provision and many other firms. The many testimonials which the Company publish shews the appreciation of the customers. The following are some of the purposes for which casks and barrels are made by the machinery supplied by Messrs. RansomeSoda, alkali, cement, vinegar, chemicals of all sorts, liqueurs, white lead, fish, butter, soaps, gunpowder, fruit, beer, wines, palm oil, molasses-and one could continue the list almost ad infinitum. It will thus be seen what a large part cooperage machinery plays in the industry of the country. It is no wonder that there was an insistent call for machinery to replace the slow and expensive hand methods of the past. The demand was not only in Great Britain, but all over the world. To adequately meet the want, several conditions had to be fulfilled by the machinery introduced, among which might be mentioned: Economy-The machinery must effect economy in labour and cost. Efficiency-The work produced must be equal at least to the hand-made cask or barrel. Simplicity-The machines must be so simple that they can be operated by semi-skilled or unskilled labour. These essentials have been amply fulfilled by the machines employed in the various operations necessary to convert the logs into the complete cask or barrel. Modern competition demands cheapness and rapidity of production, and any firm that uses casks and barrels to any extent must meet competition by the most efficient methods of manufacture available. A description of the various machines would fill considerable space. There are the various circular and other self-acting machines which cut and prepare the staves with the minutest precision, patent backing and hollowing machines for various kinds of staves, hydraulic stave press for bending staves into the necessary shapes, patent universal stave jointing machines, disc stave jointing machines for various kinds of staves, tonguing and grooving machines, steaming and firing cones, patent stave drying oven, combined with chiming, crozing and printing machines, patent barrel raising machines, setting up apparatus, hydraulic trussing machines, chiming, crozing and howelling machines, cleaning-off machines, patent hydraulic hoop driving machines, head rounding machines, multiple hoop punching and shearing machines, hoop splaying, bending and rivetting machines, wood hoop bending machines, bung hole boring machines, automatic power barrel hoist, circular and band saw sharpening machines in connection with the barrelmaking industry. These are some of the principal machines. In the manufacture of barrels, etc., there are produced large quantities of dust and shavings, and Messrs. Ransome have produced an ingenious patent cyclone dust collector, which obviates this nuisance. The general keynote of the testimonials from users of the machines is economy, comprised in saving in loss in manufacture, economy of labour, simplicity of operation, equality of work, low cost of maintenance. The following will shew the great output capacity of the machines The cross-cut saw for headings will, worked by a lad, cross-cut enough heading for from 2,000 to 4,000 casks per day. One of the cylinder stave saws will dispose of up to 4,000 staves per day. The backing and hollowing machine, with automatic feed, for cylinder or straight-sawn staves, will deal with from 20 to 50 staves per minute according to their length. The saw stave jointer has a production capacity of up to 1,700 hogshead staves in eight hours, while the universal stave jointing machine has a great capacity; those supplied to Thames and Medway Cement Manufacturers by Messrs. Ransome being capable of producing over 100,000 barrels per week. The disc stave jointing machines are equally prolific in their output capacity. These few samples are typical of the other machines, not only in their large output capacity, but in their simplicity and safety, an unskilled lad being able to work them satisfactorily. Quite recently a large plant for making tar barrels has been supplied to the Agwi Petroleum Corporation, Ltd., of Fawley. Messrs. Ransome, Ltd. (whose catalogue is stated by an expert to be the most complete treatise on the cooperage industry that has ever been published) are doing an important work towards the development of various industries by placing before the manufacturing public the means of successfully competing with rivals in the world market. The Problem of Corrosion Continued from Page 36. ance quite unprecedented and the steels which are to-day being produced to withstand corrosion are far in advance of the earlier forms of stainless steel, which are chiefly martensitic. The newer corrosionresisting steels are austenitic, i.e., they are softened by quenching from a high temperature, as in the case of manganese steel, whilst the acid-resisting irons have been also greatly improved recently, both from the point of view of homogenity and toughness, resultant upon careful methods of heat treatment. Experts are looking for some very useful surprises for many industrialists, as a result of this Congress. |