As the rare descent of Meteorites or Aërolites affords us the only real tangible evidence we possess respecting the mineral constituents which exist beyond the limits of our own globe, a great degree of interest must always be attached to these stray visitors ; and although much has been written on the subject at different times, it has hitherto taken the form either of a bare catalogue of the date and place of occurrence ; or of scattered notices dealing only with individual cases. My desire is to collect these various records as far as they relate to each meteoric stone which has been known, or has been said to have fallen in Great Britain, and to endeavour to give as complete an account as possible of every instance; including not only the historical facts, but also notices Of mineralogical observations and references to authorities.

This is a mere fragment of gneissic rocks which is imbedded between the granite of Roeness and the igneous rock which lies to the east : but so different are these entrapped rocks from the ordinary gneiss of Shetland, and so violent a twist do they seem to have received athwart of their normal strike, that the enquiry rises-whence did this fragment come ?

A spectator looking west from the top of Ornsfield, gazes seaward upon a mere heap of ruins ; while, looking landward, he also sees little else,-so riven and twisted are the rocks by the intrusion of dykes of porphyry, and so shattered and toppling from the invasion of the sea.

At Mr. Collins's request I submit to the members of the Mineralogical Society the following preliminary notice of substances which I have collected during" my somewhat extensive wanderings about Scotland.

In the case of several of the substances described, it will be seen that I do not by any means bring them forward as being without doubt new minerals; of that, I have not satisfied myself, and still less can I hope to satisfy others, until specimens more fitted for absolute deterrmination are obtained, and that in a quantity larger than what I have as yet had to operate upon.

The noting and describing these substances now, will enable others to lend their aid in the work.

The blue substance first came under my observation many years ago in one of the Slickensides, in the first quarry opened for the supply of Abriachan granite, and situated by the side of the road leading to Abriachan,-a somewhat isolated district amongst the hills overlooking Lock Ness.

It was then seen in purplish-blue spots, dotting here and there the surface of the rocks which had been exposed to considerable weathering, and over which water had poured freely.

Dr. Haughton, by his numerous analyses of the black mica of the Irish granites, may be said to have established the specific individuality of the lepidomelane of Hausmann.

That mineral his analyses showed to differ from Biotite in its great excess of ferric oxide and its comparative deficiency of ferrous oxide and magnesia.

Some time since Prof. Ruskin kindly sent me a specimen of goldquartz brought from New Zealand by Mr. H. A. Severn, giving me leave to cut thin slices for the microscope, and asking me to examine the same. The result seems to me of some interest, and Mr. Ruskin has kindly consented to my bringing it before the Mineralogical Society, together with a notice of a strangely beautiful gold occurrence, described by Mr. Severn as disclosed by blasting in one of the New Zealand gold reefs.

Since my former communication to the Mineralogical Society I have been endeavouring to obtain a sufficient quantity of the pure mineral therein described to complete my analyses. Plenty of what certain dealers have been selling as Penwithite is obtainable from the rubbish heaps at Wheal Owles, but this is mostly dark-brown—nearly or quite opaque, pitch—like in appearance, and of very variable composition-the silica alone varying from 22 up to 57 p. c., and the sp. gr. often being as high as 3.4.

The true mineral is sometimes attached to masses of such material—it is highly vitreous and transparent, from dark amber to reddish-brown in colour, H. 3.5 and sp. gr. only 2.49—a remarkable circumstance considering the large amount of manganous oxide present.

About a year since I received from our associate Mr. Alfred Davies, of St. Agnes, a dark-brown mineral which was supposed to consist largely of sulphide of tin. As it differed greatly in appearance from the socalled tin pyrites, I at once felt interested in the supposed new mineral, and commenced an analysis which I have lately been able to complete.

It is generally granular in appearance, dark-brown, translucent very slightly on thin edges, infusible B.B,, soluble more or less completely in aqua regia, &c.—in fact its properties differ but little from those of an ordinary dark variety of blende, except that with careful manipulation it yields a bead of tin when treated with reducing agents on charcoal.

It is only within the last century that the Cingalese have become the most astute judges upon all matters relating to gems in their uncut or natural state. That this is so is proved by the number of remarkable stones which previously found their way to England, unrecognized as being of any value; amongst them is the stone in question. How it could have been passed over and treated by the merchants as of no value is a mystery, unless its great size contradicted the probability of its being a gem. Such, however, was the case ; it having been sent to England mixed with the ordinary pieces of inferior Rubies and Sapphires used by watchmakers. It was sold for a mere nominal sum, as a piece of Quartz, or Crystal, and passed into a private collection of minerals, the owner of which regarded it also as a specimen of Quartz.

During the last three years I have been engaged in collecting and cataloguing the minerals of Japan. The following is a list of the species with which I am acquainted. The arrangement is according to the classification given by Dana in his System of Mineralogy.