The converse of the first sentence of the preceding extract is frequently observed. A leaf is never transformed into any other organ; but where we should expect stamens, carpels, petals, &c., leaves are often abnormally developed. All the organs of the plant are formed upon a plan, of which the leaf is taken as the type. This doctrine of Goethe has been long recognized by all botanists. And tracing the homologues of the leaf in the various forms assumed by flowers and fruit, constitutes one of the charms of botanical study to the young student. Exhalation, respiration, and circulation in plants are then glanced at by the author, before proceeding to describe the various parts of the flower and their functions. The different kinds of inflorescence and varieties of fruits and seeds come under review; and lastly, the interesting phenomena of fecundation and germination are investigated, bringing the portion devoted to organography to a close. The chapter on fecundation is extremely interesting, and is written in a popular style. "When the existence of sexual differences in vegetables was first propounded, the discovery produced general astonishment. If the most convincing proofs had not established it, if the commonest observation had not allowed every one to verify its reality, it would certainly have been classed among the most singular inventions ever issued from a poet's imagination; but the proofs were convincing. The demonstration of the existence of sexual organs in vegetables became a brilliant and unexpected fact, exhibiting a wonderful analogy between animals and plants, filling up in part the gulf which had hitherto existed between the two great classes of organic beings, yielding an inexhaustible fund of reflection and comparison to naturalists and thinking men. "The ancients had very vague ideas on this subject. Yet we learn from Herodotus that in his time the Babylonians already distinguished two sorts of Date Palmes. They sprinkled the pollen of one on the flower of the other, in order to perfect the production of the fruit of that valuable tree. Cesalpin, an Italian philosopher, physician, and naturalist, who, in the 16th century, was professor of medicine and botany at Pisa, remarked that certain sets of mercurialis and hemp remained sterile, while others were productive. He considered the first as the male sets, and the second as the female. In the 17th century, Nehemiah Grew, a learned English Fellow of the Royal Society of London, published in 1682 an anatomy of plants; above all, Jaques Camerarius, a German botanist, born at Tübingen, showed the precise use of the two essential parts of the flower, and the part that each plays in producing the fecundation of germs. In a letter now become celebrated, De Sexu Plantarum, published in 1694, VOL. IV. * P. 177. N Camerarius completely proved the great fact of the existence of the sexes in plants just as in animals. This discovery made an impression on the minds of naturalists; it was, in fact, one of the most striking victories which natural science had obtained." * The portion of the work devoted to systematic botany is preceded by a sketch of the history of botanical science from the time of Aristotle, giving an account of the labours of Grew, Tournefort, Ray, Magnol, Linnæus, Bernard de Jussieu, Adanson, Laurente de Jussieu, De Candolle, Robert Brown, Dr. Lindley, and other great botanists; and it forms a very appropriate introduction to the study of that department of the science. Dr Lindley's son has lately written to the Athenæum,' complaining of the unfair use made of his father's works in compiling the Vegetable World.' M. Figuier and his editor quote largely from Dr. Lindley's works, and adopt his classification of plants; but their obligations to him are honourably acknowledged in numerous instances, and the translator and editor pays the following tribute to his merits:†-"His knowledge of vegetable structure was extensive and profound. His indefatigable industry and unequalled powers of generalization enabled him to grapple with and bring to perfection the vast scheme of rearranging on physiological principles, after careful structural examination, the whole vegetable world. His 'Vegetable Kingdom remains a monument of immense learning, technical knowledge, and vast industry. The modern school of botanists may be said, one and all, to have been his pupils, and the system he has framed is probably the nearest to perfection which the world has yet seen. The classification proceeds in the ascending order, commencing with the Diatomacea. We should prefer De Candolle's subdivision of the class Exogens into Thalamifloræ, Calycifloræ, Corollifloræ, and Monochlamydæ, to that adopted. We were somewhat puzzled for a moment at seeing the pages in which the genera Fraxinus, Olea, Solanum, Nicotiana, Atropa, &c., are described, headed "Rosals;" but this is a typographical error, and will, no doubt, be rectified in the next edition. The engravings, we are told in the preface, are all from nature. They seem to have been drawn from living nature, and not from dried specimens, as sometimes seems to be the case in works on botany. The concluding portion of the book is on the geographical distribution of plants, and is not the least interesting portion; but want of space prevents us from giving any further extracts, for we have still to deal with M. Figuier's labours in other departments of human intelligence. Perhaps one of his most attractive productions is after all his 'Merveilles de la Science,' and those who have seen the book will not be surprised to hear that it has had a very large sale in France. It is a work still in progress, and first appears in numbers at 10 cts. each, and then in series; and if some enterprising English publisher would arrange for its republication in England-taking care to add a fuller account of those British inventions to which M. Figuier naturally devotes a more limited space than to those of his own countrymen-we have little doubt that the venture would prove remunerative. 'Les Merveilles de la Science' is a handsome quarto volume, containing a most agreeable history of the Steam Engine, Steam Boats, Locomotives, Electrical Machines, Lightning Conductors, the Voltaic Pile, and Electro-Magnetism. Doubtless many of his illustrations are fanciful; at least they represent events in the history of Science (such as "James Watt, étudiant le perfectionnement de la machine de Newcomen") which were at the time of so little importance in the eyes of the world, compared with the butcheries of successful generals, that they are not likely to have boasted a special limner; but be that as it may, the sketches of the various scenes on scientific history are very attractive, and are typical of a phase in historical studies not to be met with in any similar work. Were it only for his pleasing reminiscences of the scientific History of Britain, we could not help giving our tribute of admiration to M. Figuier's work, where the reader will find sketches of "Savery in the Tavern," "Humphrey Potter, or the Lazy Genius," "Black making experiments on Latent Heat,' various reminiscences of James Watt and the Soho Works, &c. The foreign scenes are also excellent, and the portraits, commencing with that of Bacon and ending with Ruhmkorff, appear very good, and are certainly of an order hardly to be expected in a serial at ten centimes. When we add that one of the last sketches is that of Wilde's magneto-electrical machine, which appeared in our number of last October, it will be evident that M. Figuier is not unconscious of the latest scientific novelties. age as Indeed it is not likely that he ever will be far behind his long as he continues to compile and publish another work before us, L'Année scientifique et industrielle, '† to which we shall now devote a few closing remarks. The frontispiece to M. Figuier's "Annual" represents the eruption of the Volcanic Island of Santorin, copied from a photograph, and its contents comprise accounts of all events and discoveries of note in every branch of science, with accounts of the proceedings of scientific societies, and obituaries of eminent men; indeed it greatly resembles our own "Chronicles of Science." M. Figuier should, in future, request some English friend to look over * Les Merveilles de la Science, ou description populaire des Inventions modernes.' Par Louis Figuier. Paris: Furne, Jouvet & Cie. 1866. L'Année Scientifique et Industrielle, ou Exposé Annuel des Travaux Scientifiques, des Inventions et des Principales Applications de la Science à l'Industrie, aux Arts, &c.' Par Louis Figuier. (11me Année, 1866.) Paris: L. Hachette & Cie. 1867. N 2 his work, and rectify errors in English names, such as that of Brande, which he spells Brandes, for he must know that the brotherhood between the scientific circles of France and England is becoming more and more intimate every year, and increased accuracy is required in the record of their respective labours. It is to promote the closer union of the scientific men on either side of the Channel that we have chosen M. Figuier as the subject of this memoir. We might, it is true, have selected Frenchmen more deeply versed in some particular branch of science, and better known in our own scientific sphere; but we think that the account we have given of the useful and varied labours of M. Figuier, the favour with which his treatises have been received in England, and the influence they are likely to exercise upon his own vivacious and somewhat volatile countrymen, sufficiently justify our choice in this respect, and we hope to receive many more works from the pen of the same zealous and accomplished author. V. THE VENTILATION OF COAL MINES. By ROBERT HUNT, F.R.S., Keeper of the Mining Records. THE terrific explosion of fire-damp in the Oaks colliery near Barnsley, by which more men were killed than were ever sacrificed in any mine in the world at one time, and the scarcely less sad calamity at the Talk-o'-th'-Hill colliery in North Staffordshire, have forcibly drawn attention to the modes employed for the extraction of coal from the inclosing rocks. The results of the inquiries instituted have served to prove that, in the colliery where the greater number of lives were lost, all the arrangements were such as would be produced under the most satisfactory management; whilst in the other there were evidences of neglect arising from the lax system of discipline which prevailed. Therefore, in re-examining the question of ventilation-which appears necessary, since we desire to remove some of the numerous errors which prevail-we may keep before us with advantage these Yorkshire and Staffordshire collieries as representing respectively a good and an imperfect system of coal-mining. The Inspector's reports, which have been published regularly for ten years, inform us that about 1,000 men are killed annually in this country, in raising our coal from its bed. This has been long known, but, excepting by those who are directly brought in contact with the coal-mining population, it has passed unheeded. It is only when a great catastrophe occurs-and scores, or it may be hundreds, of men are killed-that public attention is aroused, and directed to |