It has often struck me that much more might be learned from the study of the secondary forms of crystalline minerals than we now know respecting the circumstances under which they were produced. Some years ago being chiefly acquainted with calcite as it occurs in Derbyshire, where the crystals are usually of the so-called dog-tooth shape, my attention was much attracted by the difference in the form of the crystals in Devonshire and Cornwall, where we so often meet with six-sided prisms. On reflecting on this difference I could not give any more satisfactory explanation than that the conditions under which they were formed must have been very different in some important particular. Various experiments, made both before and afterwards, sufficed to indicate at all events some of the possible causes of such a difference in the form of this mineral, but at the same time showed clearly that much special research would be required before we could draw such definite conclusions as could be desired.

The examination of the rhyolite exhumed by Dr. Henry Hicks, F.G.S., from the conglomerate of the Pebidian formation of St. Davids, Pembrokeshire (Quart. Journ. Geol. Soc., May., 1878, p. 153), recalled to my mind certain rocks from other localities which bad found a place in the large and important petrological collection in the British Museum, which I thought might prove to belong to the same group. Among these, some fragments brought from Bouley Bay, Jersey, by Wm. Carruthers, Esq., F.R.S., whose attention they attracted, interested me especially. It was found, however, that they had not been collected with the view of illustrating the rock in all its varieties, so further examination was postponed until an opportunity occurred to procure more material.

The late eminent palæontologist, Mr. Salter, F.G.S., characterized the portion of the lovely valley of the Mawddach, at, and near the Falls of the Cain and Mawddach Rivers, "a perfect geological puzzle."

Certain it is, that touching Tyddyngwladus, the survey maps are greatly at fault; and, that the rocks, thereabouts, most of them, are of precambrian age.

Dr. Hicks, F.G.S., has hit upon the truth, approximately, I think, in what he calls Dimetian at St. David's, (as applied to the lowest beds of this district.)

After more than a year's unceasing investigation of these puzzling rocks and their associated minerals (chiefly with reference to the modes of occurrence of the "precious metals").

I have lately had the opportunity of conversing with one of our members, Mr. Jos. Jewell, who has been making an inspection of some parts of the island of Cyprus for mining purposes, and having been called upon by other parties to report on a number of mineral specimens brought from that island, I have thought that a short note on the subject might be of some interest to the members generally.

So much has been said of the mineral riches of the island, that I was astonished at the comparative poverty of the specimens brought home, and also at the very small number of mineral species which the island has so far yielded.

Referring to my notes in number 3 of the Mineralogical Magazine for 1877, I observe one or two little matters which I hoped the march of time would improve. One desideratum, a good hotel, the Hotel d'Anniviers, has been established at Vissoie, and M. Monnet, the landlord, is a man of intelligence, and, without pretending to scientific lore, has much information concerning the mining, geology, botany and history of the neigbbouring valleys. Jean Martin, my guide in many a tough scramble, has married, and established a small restaurant with a couple of bedrooms at Vissoie, which place may now fairly be said to have become a centre for many interesting excursions ; as, to the Bella Tola, whence the panorama is very grand,—to the Cols leading from the Grimenz Thal to the Val de l' Arolla and Evolena, and also to the Turtman Thal, and so across to St. Niklaus in the Zermatt valley.

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.

The Iron Crystals described by Mr. Beardsley in the present volume of the Mineralogical Magazine (p. 223) exhibit the remarkable structure illustrated in figs. 1 to 5, plate VII. Fig. 1 represents the crystals drawn natural size, and fig. 2 is a section of one of them in a plane parallel to a face of the cube—shewing the structure developed by etching. Figs 3 and 4 illustrate other modificatious of structure which have been observed in iron crystals, and for which I am indebted to Dr. C. O. Trechmann of Hartlepool, and fig 5 may perhaps indicate the ultimate molecular structure.

The accompanying map is the outcome of a survey of Shetland, conducted during part of several summers.

Almost the whole of the junctions laid down were visited by myself ; for the few that were not, and also for certain of the lines continued inland—which from an almost unbroken covering of peat and turf, are more or less conjectural—I am indebted to Dr. Hibbert's narrative.

To Professor Geikie's map of Scotland I am indebted for the southern limit of the isolated mass of sandstone of the Lerwick district.

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.

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.