Berk., the reticulations are gill-like, and the ochraceous head rivulose. This occurs at all seasons, and appears to be the more frequent of the three.

The curious fungus (Fig. 3), figured from a beautiful drawing by Kurtz, belongs to the imperforate set. It is Cynophallus bambusinus, Zöllinger, and, like the Dictyophore just mentioned, grows on the trunks of bamboo in Java. It is gregarious, with an elongated conical subacute receptacle, strongly papillose, and of a deep purple red; the stem is fistulose and rose coloured, the volva white. The head is sometimes crowned with a portion of the ruptured volva. We have a species of the same genus in Great Britain, but it is not of very common occurrence, though one of our most interesting fungi.

We now come to the fourth group, in which the receptacle is more or less deeply divided, the divisions being distinct above and not united, as in the columnar Clathri, with which they are closely connected. Lysurus Archeri, Berk., beautifully figured in the botany of the antarctic voyage, is quite destitute of a stem, and differs mainly from Clathrus triscapus in the divisions not being united above. Its close affinity, however, with Aseröe, to be noticed presently, is indicated by the tip being very shortly bifid, though the divisions do not seem to separate readily from each other. In other species, as in Lysurus mokusin and L. aseröiformis (Fig. 10), there is a long distinct stem. The volva of the former is eaten by the Chinese, but often proves poisonous; and when calcined, as mentioned above, the plant is a favourite remedy for gangrenous ulcers. In Lysurus aseröiformis (Fig. 10), as the name implies, the divisions of the receptacle are so deep, that it is essentially a highly stipitate Ascröe. It was found by Sieber in Australia. The receptacle is of a beautiful rose colour, inclining in parts

to carmine.

Aseröe is distinguished from typical Lysuri by the deeply bifid rays of the receptacle. Aseröe rubra (Fig. 1) appears to assume a great number of forms. I had the advantage of comparing numerous specimens with the late Mr. R. Brown, and we both came to the conclusion, that A. pentactina, and the very different looking plant as figured by Labillardiere, and which once came up in some soil from New Holland, at Kew, were in reality the same species. A. rubra (Fig. 1) is a most elegant fungus. "The pileus," after a description by M. Leichardt, by whom the drawing copied in our coloured plate was made, "is divided into eight rays, each of which is forked, the divisions being acuminated and slightly twisted. The centre of this pileus is perforated by a rather large irregular aperture, by means of which there is a communication with

the cavity of the stipes and the atmosphere. A dark brownish moist matter covers the upper surface of the disc. The rays are of a fine bright scarlet above, while the under surface and stem are of a pale rose colour. An attentive observation with a lens exhibits minute openings, one at the base of each ray, which communicates with larger holes immediately beneath the upper layer of the disc.

The other species figured Aseröe Hookeri, Berk. (Fig. 7), was originally found by Dr. Hooker on clay banks or hills near the Bay of Islands, New Zealand. It differs essentially in the transversely wrinkled stem; and the mode in which the half rays of each pair are connected with each other, calling to mind the arrangement in the column of Asclepiadice. The rays are strongly grooved beneath, and perfectly distinct from the stem. Two forms are found, the one which we owe to Mr. Colenso, of a more or less deep red, the other of a metallic green.

An Aseröe occurs in Ceylon in which the rays seem to be more irregular, paving the way for Dr. Montagne's genus Calathiscus, in which all the rays are equal. Calathiscus sepia, Mont. (Fig. 6), was found near Ootacamund in Western Hindostan, near the roots of trees in moist woods in rainy weather in September. The stem is about two inches high, and confluent with the receptacle, which is dilated so as to present the form of a calathus. The margin is divided half-way into about twenty equal divisions, which are greatly attenuated and curled inwards at the top; the volva is globular and white, the rest of the fungus pale pink, with the exception of a narrow ring which surrounds the open top of the stem, which is the hymenium.

Several other genera might have been added, but enough are given to show the general character of a highly interesting group.

The Figures represent-1. Aseröe rubra, half natural size; 2. Simblum flavescens, one-third natural size; 3. Cynophallus bambusinus, half natural size; 4. Dictyophora phalloidea, half natural size; 5. Clathrus triscapus, half natural size; 6. Calathiscus sepia, three-eighths natural size; 7. Aseröe Hookeri, half natural size; 8. Clathrus pusillus, half natural size; 9. Ileodictyon gracile, three-fourths natural size (Ileodictyon cibarium, the New Zealand species, is much larger); 10. Lysurus aseröiformis, two-thirds natural size.

ON THE APPLICATION OF SCIENTIFIC DISCOVERY TO THE USEFUL ARTS.

No. II.

BY PROFESSOR M'GAULEY.

IN a recent paper I endeavoured to recall to the mind of the reader some important applications of science, having reference especially to a saving of labour. I shall now direct attention rather to the effect of scientific discovery in the prevention of injury to health, or of pecuniary loss from unnecessary waste, and in the production of new and valuable materials. On this, as on the former occasion, only a few examples can be selected from the many which testify to the advantages conferred by science on mankind; but, wherever we turn, we are met by undoubted proofs of its effect, in diminishing the inconveniences under which we labour, or augmenting the sources of our enjoyment. In treating this subject, the difficulty is, not to find matter, but to make selections from it, where so many interesting and important examples force themselves on our view.

The amount of fuel which, in the shape of coal, has been provided for us is very great, but the supply is not inexhaustible. On public grounds, therefore, it becomes highly desirable to economise this important substance, but still more from considerations connected with private interest. In almost every article we purchase, the cost of its production depends, either directly or indirectly, on the cost of the fuel which has been employed in preparing it. With our ordinary modes of producing combustion, the waste of heat is enormous, and therefore the cost of the fuel is greatly augmented. This becomes apparent, if we consider the vast amount of heat carried away, along with the products of combustion, by the chimney; the effect really obtained from the fuel being due only to the excess of the heat produced by combustion over that existing at the time in the body to be heated. It is, for example, clear that, were the water in the boiler at the same temperature as the interior of the furnace, no additional heat would be communicated to it; and, by consequence, the whole of the heat produced by combustion would be carried up the chimney and wasted. The high temperature which, therefore, is required to maintain a difference between the temperature of the body to be heated, and that of the source whence the heat is obtained, is in itself another source of waste. The greater the heat of the furnace, the greater the loss

by radiation, and the greater the current of heated air which passes off into the external atmosphere; so that the very effort made to obtain a sufficient temperature renders the attainment of it still more difficult, and greatly increases the quantity of heat evolved without giving rise to any useful result.

These disadvantages attending combustion, as ordinarily effected, have long been a source of regret to manufacturers and men of science; and numberless efforts have been made, if not to get rid of them altogether, at least to diminish the loss which they cause. But very little was done in furtherance of this most desirable object, until the principle of the regenerative furnace was successfully applied. The evil was very difficult to be cured. The loss is chiefly caused by a great quantity of the heat being carried along with the products of combustion into the chimney: but lessening or impeding the current in the latter, by diminishing the supply of air, would render the combustion less intense, and therefore insufficient. The application of a principle, however, which has been long known, and in use in other ways, afforded a solution to the important problem, and without interfering in any manner with the amount of air supplied for combustion; while, at the same time, nearly all the heat contained in the products of combustion is intercepted and retained. The means employed for the purpose are so simple, that it is surprising their application was so long delayed. But so it is with nearly all great improvements in science. They depend on the easy application of some simple, and often well-known, principle: and they do not strike the minds of experimentalists at once, simply, perhaps, because it is intended that our intellectual development should in every way be gradual-one great truth in science not being rendered obvious to inquirers until those already known have been worked out and utilized.

The regenerative furnace, the invention of Mr. Siemens, thoroughly economises heat. It is believed to lessen the consumption of fuel to the extent of from forty to sixty per cent.; and, which is a matter of scarcely less importance in the production of iron, it allows inferior ores to be used. Other and greater advantages also accompany its use. By means of it a very intense heat may be obtained from the inferior kinds of fuel; and since only the gases obtained from the latter are brought into contact with the body to be heated, any deleterious ingredients it may contain cannot produce an injurious effectwhich allows fuel, of little or no value hitherto, to be used with the very best results. As the gases and vapours evolved from the fuel are entirely consumed, not only is the smoke nuisance abated, but valuable matters, which ordinarily pass off uncon

sumed, to the great annoyance and injury of the neighbourhood, are rendered effective in the production of heat, and therefore in economising fuel.

Such being the advantages of the regenerative furnace, we cannot wonder at its having already come into very general use. The defects of the very best ordinary furnace are so great, and its incapability of applying to a useful purpose any more than a small portion of the excess of its temperature above that of the body to be operated on is so irremediable, that there is good reason to believe it wastes at least seventyfive per cent. of the effect producible from the fuel: a fact which clearly shows how desirable it is to supersede it by a better arrangement.

The general principle on which the action of the regenerative furnace depends, is easily understood: the details, which vary, though but slightly, with circumstances, are comparatively of but little interest, and, therefore, need not be noticed here. This furnace consists essentially of two parts; the gasproducer, which affords the heat, and the regenerator, which prevents it from being wasted. It is, in reality, a gas-furnace, and the fuel is used almost exclusively for the production of gas, the combustion of which is to furnish the heat required for the manufacturing purpose. The arrangements are such that the carbonic acid, formed by combustion in the furnace which acts as a gas-producer, is made to pass through incandescent fuel. It is thus changed into carbonic oxide, which passes off along with the other inflammable gases that have been evolved from the fuel, and also with the air which is heated by combustion of the carbon during the formation of the carbonic acid, most of which with the ordinary furnace escape uncombined, and, therefore, without evolving heat, into the chimney, and are lost. These gases, raised to a high temperature by the burning fuel in the producer, pass into the chamber where they are to be consumed, and along with them hydrogen and carbonic oxide, furnished by decomposition of some vapour of water, that has been transmitted through the intensely-ignited fuel in the producer along with the air required for the support of combustion. The amount of this gaseous mixture, and, therefore, the amount of the heat evolved, are completely under control, as these depend on the quantity of air admitted into the furnace of the producer.

After the gases have been burned in the chamber, and the heat set free by them has been applied to the manufacturing or other purpose for which it is required, they are not allowed to pass directly into the atmosphere; since this would cause a large quantity of the heat which has been obtained from the fuel to be lost. Under the combustion-chamber are placed