Here, then, we have important elements of economy, at the very beginning and end of the manufacture, if end that can have which has the attribute of a renewal of usefulness. Galoshoes may be called in as worn out sovereigns and shillings are now, and returning to their mint, be melted up and re-stamped for renewed circulation. Another advantage in the manufacture is, that the same tools are employed for its various branches, and the same operatives can be turned from the making of one description of an article to another, without delay or expense. A girl, for instance, who may be engaged as the maker of garments one day, may become the next a trunk, a harness, or a shoemaker; and on the third, find herself occupied in pressing out of the soft and ductile mass brooches, and other articles of adornment, which being afterwards vulcanized, and thus rendered almost imperishable, may serve to encircle the neck, clasp the arm, or hang pendant from the waist of Britain’s fairest daughters. The machinery employed in the manufacture of India-rubber, since the first attempts to work it, has been subjected to variation and gradual improvement. Numerous expedients and divers machines were early tried for chopping, grinding and spreading the gum, and also for flowing it in a liquid or semi-liquid state, which have been abandoned. It is now generally agreed by manufacturers in this business, that the machinery is as near perfection as can be attained; that is to say, they are all satisfied with it. But in this age of improvements, we might see to-morrow one machine doing the work of two or more, and all calculations as to perfectibility obliterated, but to begin again upon fresh data. It must however be admitted that it is of the most simple kind, doing the work well and with astonishing rapidity, although requiring great mechanical power, owing to the toughness and tenacity of the gum. The machine used for cutting and washing the gum is the same as that employed by paper-makers in cutting rags. A large proportion of the India-rubber was nearly useless from the quantity of bark in it until this engine came into use. Gum-elastic or India-rubber can be readily mixed or combined with almost every other substance. It may be mixed with other gums, oils, coal-tar, carbon, and with the earths, and oxides or pulverized metals or ores. It can likewise be combined with all fibrous products.