108 THE METEORITES, — THEIR ORIGIN AND CHARACTER. 



of space through which they moved, gave rise to a variable amount of metamorphism. 

 In some few cases, when the whole mass was fused, all evidence of a previous history has 

 been obliterated ; and on solidification a structure has been produced quite similar to that 

 of terrestrial volcanic rocks. Such metamorphosed or fused masses were sometimes 

 more or less completely broken up by violent collision, and the fragments again collected 

 together and solidified. Whilst these changes were taking place, various metallic com- 

 pounds of iron were so introduced as to indicate tliat they still existed in free space in the 

 shape of vapour, and condensed amongst the previously formed particles of the meteorites. 

 At all events, the relative amount of the metallic constituents appears to have increased 

 with the lapse of time, and they often crystallized under conditions differing entirely from 

 those which occurred when mixed metallic and stony materials were metamorphosed, or 

 solidified from a state of igneous fusion in such small masses that the force of gravita- 

 tion was too weak to separate the constituents, although they differ so much in specific 

 gravity. ... I therefore conclude provisionally that meteorites are records of the exist- 

 ence in planetary space of physical conditions more or less similar to those now confined 

 to the immediate neighborhood of the sun, at a period indefinitely more remote than 

 that of the occurrence of any of the facts revealed to us by the study of Geology — 

 at a period which might, in fact, be called 2^'>'<^-i'^>'i'<^strial."* 



These views of Mr. Sorby were again given to the public, with additional 



matter, in 1877. He then stated that 



" it is very probable, if not absolutely certain, that the crystalline minerals were chiefly 

 formed by an igneous process, like those in lava, and analogous volcanic rocks. . . . 

 Some [of the spherules] are almost spherical drops of true glass in the midst of wliich 

 crystals have been formed, sometimes scattered promiscuously, and sometimes deposited 

 on tlie external surface, radiating inwardly ; they are, in fact, partially devitrified glob- 

 ules of glass, exactly similar to some artificial blow-pipe beads. . . . I . . . argue that 

 some at least of the constituent particles of meteorites were originally detached glassy 

 globules, like drops of fiery rain. . . . We cannot help wondering whether, after all, 

 meteorites may not be portions of the sun recently detached from it by the violent dis- 

 turbances which do most certainly now occur, or were carried off from it at some earlier 

 period, when these disturbances were more intense." f 



David Forbes stated that meteoritic stones are seen under the micro.seope 



" to be an aggregation of fragmentary matter resembling a volcanic ash or breccia, in 

 which, whilst some of the particles have been in a molten state (the presence of both 

 glass and air cavities in them indicating that they were in the molten state when gases 

 or vapours were being given off), others show no signs of fusion ; so that the structure of 

 meteorites confirms the views that they have been formed out of the debris of some pre- 

 viously existing larger mass, or even out of the ruins of some planetary body."$ 



Dr. Stani.slas Meunier has done much work in the study of meteorites, 

 published a large number of papers, and holds some decidedly original views 

 regarding their origin. He maintains that all have a common origin, and 



* Gcol. Mag., 1865 (1) ii. 4i7, iiS. f Nature, 1S7G-77, xv. 495-498. 



+ Geol. Mag., 1S72 (1), ix. 223-235. 



