Transactions of the Society Instituted at London for the Encouragement of Arts, Manufactures, and Commerce, Volúmenes 37-38

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Página xxvii - Society, a cheap and Portable Drag, or other machine, superior to those now in use, for the purpose of taking up, in the best and most expeditious manner, and with the least injury, the bodies of persons who have sunk under water; — the Gold Medal, or Thirty Guineas.
Página 59 - S wet brush, and the facility with which the artist may scrape off the colour from any particular part, by means of the point of a knife or other convenient instrument, and thus heighten and add brilliancy to the lights in his painting, more expeditiously...
Página 52 - Patentee makes use of good cast steel, in preference to any other sort of steel, for the purpose of making plates, cylinders, circular or other dies, and more especially when such plates, cylinders, or dies are intended to be de-carbonated. For the reason given above, the steel is de-carbonated, solely for the purpose of rendering it sufficiently soft for receiving any impression intended to be made thereon. It is therefore necessary that, after any piece of steel has been...
Página 26 - This they efl'ect by making, at sunset, two longitudinal incisions from below upwards, without penetrating the cavity, with an instrument that has two points as fine and sharp as a lancet. The incisions are repeated every evening, until each capsule has received six or eight wounds, and they are then allowed to ripen their seeds. The juice which exudes is collected in the morning, and being inspissated to a proper consistence, by working it in an earthen pot in the sun^s heat, it is formed into cakes...
Página 52 - The stratum of decarbonated steel should not be too thick for transferring fine and delicate engravings; for instance, not more than three times the depth of the engraving ; but for other purposes the surface of the steel may be decarbonated to any required thickness. To decarbonate it to a proper thickness for a fine engraving, it is to be exposed for four hours in a white heat, enclosed in a cast-iron box with a wellclosed lid.
Página 61 - ... of a size somewhat smaller than the paper, turn up the edges of the paper, and paste them on the back of the slate, and then allow the paper to dry gradually. Wet, as before, three more sheets of the same kind of paper, and paste them on the others, one at a time ; cut off with a knife what projects beyond the edges of the slate, and when the whole...
Página xxix - Licences for that purpose under the Hand and Seal of the Governor or Commander in Chief of the...
Página xi - To the person who shall discover to the Society the cheapest and most effectual method of raising water in quantities sufficient to be beneficially employed for the purpose of irrigating land superior to, and cheaper than any other method now in use ; — the Gold Medal, or Fifty Guineas, A model, on a scale of one inch to a foot, with...
Página xv - LEAD. To the person who shall discover to the Society the cheapest, safest, most durable, and most easily fusible composition, fit for the purpose of glazing the ordinary kinds of earthen-ware, without any preparation of lead, and superior to any hitherto in use ; the gold medal, or thirty guineas.
Página 82 - ... valves for allowing the foul air to escape. The operation of this self-acting ventilator is as follows : Each tank or butt is half filled with water, which flows freely from one to the other through the pipe d. The quantity of water running alternately from each depends upon the motion of the ship. When one of the tanks is elevated by the ship's motion, the water will run through the pipe d into the depressed tank, and thereby discharge as much foul air through the valve / as the additional

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