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acid action Agassiz air-pump Alps already ancient animals appear become belonging Boyle called carbonate cause character coast collected common complete connected considerable considered contains continued cylinder deposits described direct effect elevation engine England Europe example existence experiments extended fact feet fishes formation former fossils glacier heat height important improvements Indians interesting iron islands Italy known lake land latter less lower manner mass means mineral mountains native nature nearly northern nummulitic observed obtained occur origin passed period plants portion present probably produced Professor recent regions relations remains remarkable respect river rocks seen shew side similar Society species specimens stream successive supposed surface terraces tion tree tribes valley various vegetation veins whole wood
Page 333 - New Experiments Physico-mechanical, touching the spring of the air, and its effects ; (made for the most part in a new pneumatical engine) written .... by the honourable Robert Boyle, Esq.
Page 198 - Scarcely, however, did I ever wish to change such hours of freedom for all the luxuries of civilized life ; and, unnatural and extraordinary as it may appear, yet such is the fascination of the life of the mountain hunter, that I believe...
Page 239 - On the same occasion, the current tore away from the abutment of a mill-dam a large block of greenstone-por phyry, weighing nearly two tons, and transported the same to the distance of a quarter of a mile. Instances are related as occurring repeatedly, in which from one to three thousand tons of gravel are in like manner removed to great distances in one day*.
Page 387 - ... frequently yields from six to eight new trees and more. For the production of the manna, young and strong shoots are requisite ; but they are not tapped before the tree ceases to push forth any more leaves, and the sap consequently collects in the stem.
Page 97 - I use a common reverberatory furnace heated by a coke fire with its hearth covered with a compact bed of native carbonate of magnesia three or four inches thick. Several clay steam-pipes are introduced through the roof of the furnace so as to throw a current of heated steam over the whole width of the hearth; these pipes are connected with a steam-boiler by a series of fire-clay tubes kept red hot. The sulphate, broken into pieces of about half an inch in diameter, is spread over the lining of carbonate...
Page 187 - Were we to assume, as our standard of the importance of any investigation, the relation which the subject of it bears to the progress of civilization, there is no one which would reach higher than that which refers to the subject of steel ; seeing that it is to our possession of the art of producing that inestimable material that we owe nearly the whole of the arts. I am desirous of contributing a few ideas on the subject, with a view to our arriving at more distinct knowledge as to what (in a chemical...
Page 100 - The withdrawn charge is then lixiviated with hot water, and the solution of aluminate of potash or soda thus obtained is treated with carbonic acid, as before described. The lining of the cylinder should be examined occasionally, and kept in repair, so that the fire-clay may not be corroded by the alkali. Provided the charge of alumina in the cylinder is readily and equally...
Page 252 - Nasmyth he was fortunate enough to find a mechanist capable of executing in the highest perfection all his conceptions, and prepared, by his own love of astronomy, and practical acquaintance with astronomical...
Page 188 - In order to examine this, all that is requisite is to fill a wrought-iron retort with a mixture of pure carbon and iron filings, subject it to a long-continued red heat, and receive the evolved gas over mercury. Having obtained the gas in question, in this manner, then permit a piece of polished steel to come in contact with this gas, and, in all probability', we shall then have reproduced on the surface of the steel a coat of carbon, resulting from the reunion of its two elements ; viz.