Gleanings from the International Exhibition. 399 



minium bronze to the purposes of ornamental art as well as to the 

 manufacture of objects of utility is strikingly exemplified in the 

 magnificent series of articles exhibited by Bell Brothers (18). One 

 of the strangest properties of this singular alloy of copper and 

 aluminium is that after being forged it is annealed by precisely the 

 reverse treatment to which iron is subjected, as it is heated to dull 

 redness and then plunged into cold water. 



British Gold and Silver. — The value of the precious metals 

 that may be obtained from British sources is but beginning to be 

 appreciated. Cox of Derby (71), shows a mass of silver weighing 

 nearly 2000 ounces, obtained from lead ores, and the Vigra and 

 Clogau Mining Company (383), exhibit ingots of gold of 123 ounces, 

 showing the weekly yield obtained from these mines. 



Tensile Strength op Iron. — At the end of the case of iron 

 manufactures from the Round Oak Iron "Works of Lord Dudley 

 (332), is a piece of cold rolled plate, having a sectional area of one 

 square inch, that was tested at the government dockyards, and was 

 found to support the enormous strain of upwards of fifty tons 

 before it broke. This inch bar of iron would have supported a 

 greater weight than that of 700 persons. . 



Sheet of Metal One Mile in Length. — A sheet, or shaving of 

 cut lead, one mile in length, and having an area of nearly 800 

 square feet, is exhibited by Wilmhurst's Patent Foil Company (410). 

 This is, perhaps, the longest sheet of metal ever manufactured. 



Rail One Hundred and Seventeen Feet in Length. — In the 

 open court adjoining the eastern annexe, may be seen a rail 117 feet 

 long, rolled by the Butterley Iron Company in one length. 



Gigantic Masses oe Rolled and Forged Iron. — Among the 

 stupendous masses of iron exhibited may be mentioned the forged 

 double crank shaft, weighing twenty-five tons, and designed for 

 the engines of one of the new armour-plated vessels now build- 

 ing. Forged armour-plates are also shown more than six feet in 

 width, that can be manufactured of any thickness and almost of any 

 length required, and a rolled boiler plate 112 square feet is exhi- 

 bited. 



Amorphous Phosphorus and its Practical Applications. — The 

 discovery that phosphorus is capable of existing in a condition 

 in which it is no longer spontaneously inflammable but capable of 

 being exposed to the air without change, or danger of ignition, is 

 turned to account by Bryant and May (488), who exhibit matches 

 which cannot be ignited by friction anywhere except on the pre- 

 pared surface of the box. The secret of the contrivance being that 

 the chlorate of potash compound, tipping the match, is destitute of 

 phosphorus, which in the amorphous form, is placed on the sand 

 paper, hence these matches are perfectly safe from accidental igni- 

 tion, and moreover are not poisonous. 



Pseudomorphous Crtstals. — Mineralogists are acquainted with 

 many substances which crystallize in forms that do not belong to 

 them, or are pseudomorphous ; the formation of these crystals is 



