Page:Proceedings of the Royal Society of London Vol 1.djvu/99

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stances already examined, became the subject of investigation; and the mean result of two analyses gave, in 100 grains of the earth, 48 silica, 18 magnesia, 34 oxide of iron, and 2½ oxide of nickel.

When we observe that the three other stones were found to con- tain the same elements as that just now described, only in somewhat different proportions, we may be excused from detaining the Society with the particulars of their several analyses. Nor shall we here dwell upon Mr. Howard’s manner of reconciling his results with those of the Abbé Bachelay and Prof. Barthold, any further than to state, that the inferences drawn are favourable to the supposition, that the stones they examined were of the same nature as those here described.

IV. In this section we collect some of Mr. Howard’s principal observations on this curious subject. It must be admitted, that not- withstanding the concurring evidenoe we have of the fall of some of these substances from the atmosphere, yet the fact itself is so repug- nant to what we know as yet of the operations of nature, that we are likely to pause a while before we shall venture to form any de- cided opinion on the subject. Had the fall of all these stones been attended with meteors, we should naturally combine the two phae- nomena; and. in this case Mr. Howard contends, that as these me- teors generally move in a direction nearly horizontal, and probably not very high in the atmosphere, the objection of the stones not striking deeper into the earth, owing to their accelerated velocity, would be obviated. The imperfect knowledge we have of the origin and nature of meteors may likewise be considered as an encourage- ment for inquiring further into this hypothesis.

Should these masses, after all, turn out to be the effects of some regular and simple operation of nature, it is likely that many more will be found on the surface of the earth, which will become the ob- jects of future inquiry. Meanwhile, Mr. Howard has thought proper to take a comparative view, not only of the masses of what has been denominated Native Iron in South America and Siberia, but also of every other specimen that could be met with in our collections of the substances that came under the same denomination. For a descrip- tion of these substances, together with various observations there- upon, we are likewise indebted to Count de Bournon, who seems to think, that were the particles of iron and nickel in the stones here examined so numerous as to be in contact» with each other, and were the earthy particles interposed between them wholly destroyed; as may happen by a variety of causes, the ferrugiuons cellular texture that would remain would be very similar to the native iron of Siberia and South America; both which have, moreover, by chemical analy- sis, been found to contain an ample proportion of nickel. The Count, in describing the Siberian iron, mentions the hard transparent no- dules found in the cells of that metal, which beara great resemblance to the peridot (chrysolite of Werner), the decomposition of which leaves the empty cells which we observe in all the specimens that are brought to us. Mr. Howard, on analysing these transparent nodules,