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Improvement in Wet Process for extracting Gold from Gold-ores or Ore Waste. I, Arnold Fredrik Lundstrom, of 50, Klarabergsgatan, Stockholm, engineer, do hereby declare the nature of the invention for " Improvement in Wet Process for extracting Gold from Gold-ores or Ore Waste," and in what manner the same is to be performed, to be particularly described and ascertained in and by the following statement: — The wet processes heretofore used for extracting gold from gold-ore have chiefly been based upon the solubility of the gold in materials which contain or develop free chlorine or bromine, such as nitro-muriatic acid, chloride of lime, and muriatic or sulphuric acid, &c, or in cyanide compounds, as, for instance, cyanide of potassium, &c. The object of this present invention is to extract the gold by means of solutions which, while containing or developing chlorine or bromine, also contain chlorine or bromine compounds of such metals which with the chlorine or bromine are able to form higher chlorine or bromine compounds, such as superchlorides, which, like a kind of carriers, cause the dissolving action of the chlorine upon the gold. Such suitable metals are, for instance, lead and manganese, but even the higher chlorine compounds of nickel or cobalt, as well as iron, have a favourable influence upon the extracting of the gold. Solvents of this kind, containing also higher chlorine or bromine compounds, extract the gold more easily than the compounds containing only chlorine or bromine. The gold is thus extracted easier by means of a chloride-of-lime solution acidulated with muriatic or sulphuric acid to which is added lead-chloride, PvCl 2 , which is thereby transformed into a superchloride, PvCL.; the case is analagous with regard to an addition of chloride of manganese, MnCl 2 , which by free chlorine is transformed into superchloride of manganese, MnCl 4 , and so also with the chlorine compounds of other metals which by free chlorine are transformed into higher chlorine compounds. The aforesaid favourable action of the higher chlorine or bromine compounds is explained thereby that the chlorine or bromine thereby always acts, as it were, in a nascent state, as the higher chlorine or bromine metals easily give off a part of their chlorine or bromine to the gold, which is then extracted in the form of chloride or bromide of gold, whereupon the lower chlorine or bromine compounds thus formed are transformed in higher chlorine or bromine compounds by a new accession of chlorine or bromine. In order to describe the new process more fully I shall select chloride of lead as an example of a chlorine or bromine metal acting in this manner, and a chloride-of-lime solution acidulated by muriatic or sulphuric acid as an example of a chlorine- or bromine-developing solution. Through treatment of the chloride of lime with water a solution is first obtained, the strength of which is chosen according to the condition of the ore. Thus, for ores that do not contain more than 10 gr. of gold per ton, and not too large amounts of other chlorine-consuming materials, a chloride solution of Ito 2 per cent, strength will be suitable. With richer ores somewhat stronger solutions should be used. This solution, together with muriatic acid somewhat in surplus relatively to the amount of chloride of lime, and a solution of chloride of lead to about one-tenth of the amount of chloride of lime, or some other lead compound which with the muriatic acid and chloride of lime solution forms chloride of lead, is then put into extracting-vats with the finely ground ore ; free chlorine will then evolve, superchloride of lead is formed, and the gold is extracted as chloride. From this chloride the gold is then separated in some known manner, such, for instance, as by reducing agents, electrolysis, &c. Similarly, the process is carried on if other chlorine metals than chloride of lead are used, or other chlorine-developing means than chloride of lime and an acid—such, for instance, as an electrolysed solution of chlorine metal. The aforesaid extracting process may be adopted for other than water solutions of chlorine or bromine compounds. When the ores are rich in silver special silver-extracting chemicals, such as chlorinatrium, hyposulphite, &c, are added to the extracting medium. Having now particularly described and ascertained the nature of the said invention, and in what manner the same is to be performed, I declare what I claim is : The process for extracting gold from gold-ores or ore waste, consisting in leaching same with chlorine- or bromine-containing or chlorineor bromine-evolving solutions, to which are added before or during the leaching chlorine or bromine compounds of those metals which by free chlorine or bromine can form higher and less constant chlorine or bromine compounds, superchlorides, or superbromides. Arnold Fredrik Lundstrom. Dated Stockholm, this 3fct day of August, 1897.

Improvements in the Treatment of Minerals for Smelting and other Purposes. I, Robert Fergusson Strong, of Victoria Street, London, England, inventor and civil engineer, do hereby declare the nature of my invention for " Improvements in the Treatment of Minerals for Smelting and other Purposes" and in what manner the same is to be performed, to be particularly described and ascertained in and by the following statement: — Many attempts have been made to utilise minerals of various descriptions which, owing to their granular or friable condition, are not in a fit state for ordinary use. Some of these are mixed with clay or other materials, pressed into blocks, and dried or burned in kilns before using in the reducingfurnace. This is a slow and costly operation, besides adding to the bulk a useless mass, and requiring extra fuel in smelting. Others, again, have used coal-tar and pitch to bind the minerals, and found this mixture would not stand the heat in the smelting-furnace, so that the blocks quickly decrepitated and endangered the proper working of the furnaces by blocking the outlets, and in the case of coal and other minerals of a like nature intended for block fuel the addition of coal-tar and pitch largely increased the smoke, formed clinkers in the fire-boxes, and furred and clogged the tubes of locomotive and other boilers,