Robert Mudie

The Air Robert Mudie

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1835 Excerpt: ...as a matter of necessary inference, that in reaching the top of Puy-de-dome, Perrier had passed through, and reached the top of, a tenth part of the mass or volume of the atmosphere as estimated at the bottom. This established not only the fact of atmospheric weight being always determinable by the quantity of mercury suspended in a perpendicular tube, closed at the upper end, entirely filled, and then plunged in a bason of mercury, until the column in the tube sunk down to a fixed level, but that differences in the length of this column would afford the means of ascertaining the different heights of the places at which those differences were apparent. Pascal himself repeated the experiment at the top and bottom of the steeple of St. Jacques-la-Boucherie, at Paris; and though that was a trifling height compared with that of the mountain on which the former experiment had been made, yet here again the result was perfectly satisfactory; and though 140 IMPORTANCE OF THE FACT. some of the philosophers of the time continued to controvert the doctrine which those experiments had demonstrated, and others made some attempts to rob Pascal and Perrier of the merits of it, yet justice and sound philosophy triumphed, and it was not long before those who had been at first the most opposed to the doctrines, convinced themselves of the truth of it by their own experiments. Such was the commencement of what may be considered as our rational knowledge of the atmosphere; for so long as it was supposed that there was a principle of levity in aerial matter, and in flame and smoke, and vapours of all kinds, by which they ascended in the atmosphere contrary to the well-known phenomenon by which a shower of rain, or a stone which has been thrown up, falls down, the same arguments...