uninitiated. There is no sequence. All is disorder and confusion; little assisted by any of the published descriptionsnot at all assisted by arrangement within the building.

After a general review of all the objects in the Exhibition belonging strictly to the department of mines and quarries, minerals, metals, and mineral manufactures; and after carefully considering what is meant by progress in such subjects and what is deserving of reward in such a department, we think it may be both useful and interesting to the readers of the "POPULAR SCIENCE REVIEW" to know the conclusions arrived at by an independent observer somewhat accustomed to examine and compare such matters. Whatever opinions may be expressed, the facts on which they are founded will, at any rate, be stated, and the student who has also examined the collections, may compare his impressions with the opinions here given, while those who have not been so fortunate as to see for themselves will be better off by reading this connected outline than by any study of the disjointed catalogues.

The great value, if not the only use, of collections such as have been placed in the International Exhibition must be to show, for the purposes of comparison, the sources of material wealth provided by Nature in various countries or districts. And this wealth must be shown, in order that, where it exists and has been hitherto neglected, it may be made available; and where, in two districts, it has been treated differently, the methods may be compared, and the best adopted for the future. It is desirable also that where new contrivances have been introduced, they should be made known to those concerned; and, generally, that the peculiar conditions of minerals and the varieties of wealth of different districts should be prominently presented for investigation. When, in the course of years, new discoveries of material or new applications of old material have been made, these, of course, mark progress. When new contrivances of working or manipulation have been invented, these should be clearly reported; and they also mark progress. When, as in raw material, there is no novelty, and the case hardly admits of anything of the kind, the raw material from different districts may still be so placed as to allow of better comparison. When a raw material is important, not for itself but for some manufactured material of which it is the foundation, then should the raw and manufactured materials be placed side by side.

Bearing in mind these principles, let us conduct the reader to the Exhibition, not confining ourselves to Class I., but extending our investigation to those other departments that include the same kind of objects; of these Class X. a, may be considered the most important.

The objects group themselves naturally enough under several heads, viz.:-Mineral Surveying, Mining Operations, Mineral Products, and Manufactured Minerals. Let us endeavour to follow each through the Exhibition, both of English and foreign articles. The task is not, perhaps, easy, but, for any useful purpose, we believe it is the only one.

1. Mineral Surveying and Mining Operations.-The long array of geological maps, commencing with those of the British islands, and including most of the countries in which mining operations of any kind are carried on, is one of the most important marks of progress in the Exhibition. In no department is the progress of scientific research more clearly indicated, and in none is it so manifest that the march of improvement in mining is no longer checked by those who adhere to the old Cornish maxim: "Where it is, there it is." Could one feel satisfied that the vast amount of work indicated on the geological maps exhibited is all sound and conscientious, the advance would, indeed, be little short of miraculous to those who remember the exhibition of such maps and accompanying sections in 1851. Unfortunately, these maps are, many of them, only first approximations; and it will require more labour to correct and set them right than has been taken to construct them. In this matter, however, it is certainly true that positive error is the first step on the road to truth. Where there is nothing to find fault with, no advance is made; but it is easy for any one using an imperfect map to correct it.

Among the foreign maps, the Austrian are the most extensive and showy, and some of the Prussian probably the best. The increase in the coloured portion of the maps of the Ordnance Survey of the British Islands since 1851 is not large in appearance, but the advance is real, and for the most part trustworthy. The mining plans exhibited, and the various models of mining operations, do not offer anything remarkable either in novelty of method or illustration. Certainly, they offer no proof of progress; and in this respect there has probably been little done within the last eleven years that had not been as well done previously. It is but a very short time since one of the most distressing accidents on record occurred in a coal mine, from a neglect of the very first principles of economic mining-that of having more than one access kept up to every part of a mine except the newest and most advanced headings. There is nothing in any of the plans exhibited that shows any practical advance on the old methods of winning coal or getting ores.

Although, however, there is not much new matter, there are some admirable photographs of mining and quarrying operations, especially the latter-so good as to deserve the

most careful attention. Perhaps the photographs are the most instructive, as they are certainly the most pleasing and most easily understood of all the mining and quarrying illustrations.

Of mining models there are several, very well constructed, and one that ought to have been exceedingly popular. A large gold crushing and washing machine, in the great court of the Eastern Annexe, was long unable to do itself justice, and the interest that would have attached to it was thrown away on a hand illustration with a tin basin. Important as the subject of gold-mining is, there are few noteworthy modifications of oredressing especially adapted to gold sands, if we except some very weak repetitions of old German machinery introduced as novelties. An ingenious model of the method used in some of the Hungarian mines is exhibited. There are some ingenious contrivances to prevent accident on the breaking of the chain or lifting-gear in shafts.

2. Mineral Products.-It may well be supposed that the great strength of the exhibition of minerals would lie in this direction, and it certainly does so. Very irregularly exemplified -some departments sadly weak, some ridiculously prominentsome difficult to see, and more difficult to judge of; still there is within the walls of the building an amount of material which, if it had been fairly presented, would have possessed the most absorbing interest.

Let the reader figure to himself the result had there been in the Exhibition a Court of the Precious Metals. Had all the gold exhibits been collected into one space, the mere area occupied would have helped to impress the visitor. The gilt pyramid, ridiculous in the place which it filled, would have assumed an importance and a meaning in the centre of such a court; and the various collections grouped around would have told with wonderful effect their important tale: The whole history of gold, its real properties, and its sources of value as a representative metal, would have been at once felt and understood. Never was there a better opportunity, and never was an opportunity so lost and frittered away.

In spite, however, of everything, the collections of gold, especially from Victoria, are of the most singular interest. The grains and the pepites, the small and the large nuggets, the crystals and the flat discs-all are present in abundance and variety-all are good and true. The largest nuggets are well represented in useful models, so as to give completeness to the exhibit. Besides the Victorian gold, there is much from other parts of Australia. California is not represented, but Vancouver's Island has sent an interesting series. A remarkable and interesting group of specimens is sent from the

recently discovered localities in North Wales, and there are some specimens, not without interest, from the Brazils.

Near the gold is placed the metal platinum, in lumps of a magnitude never before produced, surrounded with the still rarer metals-iridium, osmium, rhodium, palladium, and ruthenium. In this case, the manufactured platinum is exhibited by Messrs. Johnson and Mathey, side by side with the metal. The French manufacturers of the same metal have placed some fine chemical utensils in their court since the opening of the Exhibition. These were, no doubt, intended to outshine the productions of Messrs. Johnson and Mathey. They are extremely beautiful, but inferior in variety, and not superior in execution.

As an exhibition of progress, then, the precious metals, with the exception of silver (which, although there are some fine snags from Norway, is little exemplified either in ore or metal), must be considered as justifying every expectation. All that is remarkable is new, and has never been put together as a group before. All that was wanted was that the articles should have been so placed as to illustrate each other.

Another interesting group might have been made by bringing together a number of miscellaneous and mixed metals and metalliferous minerals. A beautiful series of manufactures of aluminium-a metal that will some day enter largely into use-was itself a great illustration of progress, though a final result is not yet attained. The manufactures of German silver are well illustrated, but the illustrations as usual are quite unavailable for comparison. Ores of mercury are shown from various localities. Ores of chrome, antimony ores, and other miscellaneous but valuable minerals, may be found huddled into corners unnamed and neglected amongst the multitude of more showy, but less really interesting objects around.

Copper is one of the most important and valuable of the common metals. Some of its ores exhibited are very remarkable, but are accompanied with no general account, and can hardly be said to be instructive. From Australia, the series is extremely large, and includes many specimens of great interest. From Canada, also, there is a fine series. Native copperthe rich carbonates, both green and blue, and the more common sulphurets, are all present. Had they been placed so as to be capable of direct comparison with those from other ore-producing districts, and had the various important details of the veins been duly recorded, this part of the Exhibition might have possessed considerable value. As it is, few, probably, will look twice at the long series of dust-covered minerals dotted at intervals over all parts of the building-on tables in and

near the Eastern Annexe, on the floor in Greece and Sweden, piled in a corner in France and Belgium, and only arranged in the Zollverein and Austria. Spain and South Africa, the Brazils and Portugal, and many other countries, exhibit specimens for the most part utterly unrecognizable.

To lead and zinc ores, the remarks already made with regard to copper apply in a general way. The varieties exhibited are, however, fewer and less important. There is nothing remarkable suggested as to either the ores, or the treatment of the ores, of any of these metals, or of tin.

Iron comes next in order. There is in the Exhibition no general collection of ores, and, on the whole, the modern sources of supply in England and Europe are somewhat imperfectly indicated. Still, with some search, and by wandering to some distance, a valuable series may be made out. The metal itself is largely and well exhibited. Progress might easily have been shown in this matter by a reference to the vast additions to the resources of ore, since 1851. Progress is shown in the increased magnitude of the smelting furnaces. Models of furnaces are exhibited the yield of which is said to reach, in the case of Messrs. Schneiders' works, more than a hundred and twenty tons in the twenty-four hours. For these large yields the rich hæmatites are employed. Considering the valuable series of iron ores in the Exhibition of 1851, it is much to be regretted that the Museum of Economic Geology did not take the opportunity to complete the series by a systematic arrangement of ores from the new sources.

England, of course, is not alone in the exhibition of iron; Belgium, Austria, Prussia, Sweden, and many other countries have exhibited all the varieties, and generally in a very favourable state. There is much advance observable in the manufacture of the metal, and in the magnitude of the pieces that can be cast, forged, and turned.

But the metals form only a part of the vast series of mineral products. If the precious metals deserve a court, and would have justified great exertion to bring together the various specimens for comparison, the most precious of all minerals, carbon, would have well filled another and a prominent place. Certainly, in the exhibition of minerals, carbon should have been placed first, if money value is regarded; and if variety of condition is interesting, no substance in nature can compare with it. As it is, there are scarcely two important exhibits of coal near each other.

Leaving the diamond to take its place among manufactured jewels for personal decoration, there yet remain coal and graphite among carbon minerals. The former is exhibited very imperfectly; the latter very perfectly, thanks to the recent