Abbildungen der Seite
PDF
EPUB

three weeks before the birth of one, who was destined to emulate his fame in the same department of natural history. When seven years of age, De Candolle sustained a serious attack of hydrocephalus, a disease generally so fatal in its tendency, that the present affords a remarkable instance of complete recovery, after life had been for many days despaired of.

Possessing a remarkable facility of writing verse both in French and Latin, and having at the same time a keen relish for the study of history, young De Candolle at first resolved to make literature his profession; aspiring, as the summit of his ambition, to the fame of being a great historian. But this dream of his youth was effaced by a new taste, imbibed during a residence in the country, where he amused himself with examining the plants of the neighbourhood, and with writing their descriptions, before he had even opened a single book on botany. The few pages he there read of the volume of nature were sufficient to captivate his affections for the pursuit which henceforth became the dominant passion of his life. The botanical lectures of Professor Vaucher, which he attended in 1794, increased his ardour, and confirmed him in the resolution he had formed, of devoting himself to the cultivation of botany as his primary object, to which all other sciences, as well as branches of literature, were hereafter to be deemed subordinate, and to be followed merely as recreations from severer study.

A visit to Paris, which he made in 1795, gave him the opportunity of attending the lectures of Cuvier, Fourcroy, Vauquelin, and other distinguished professors of that period, and of forming friendships with Desfontaines and Lamarck. He always prided himself in having been the pupil of Desfontaines, in particular, towards whom he continued through life to feel the warmest gratitude and affection.

The establishment of the Society of Physics and Natural History at Geneva, which took place after his return, under the auspices of the celebrated De Saussure, gave a fresh and powerful impulse to his exertions; as was evinced by the numerous memoirs which he presented to that society.

The state of Geneva being, soon after this period, absorbed into the French empire, De Candolle was induced to quit that city and attend the medical lectures in Paris ; a course of study which, tending to enlarge his views of the physiology of organized beings, contributed greatly to the success with which he afterwards cultivated the philosophy of botany. While at Paris, he founded, in conjunc. tion with his friend, M. Benjamin Delessert, the Société Philantropique. One of the first advantages resulting to the public from this institution was the distribution of economical soups throughout the different quarters of the city. Of this institution he was the active secretary for ten years ; during which period another society was also formed under his direction and management for the Encouragement of National Industry.

In 1804 he gave lectures on Vegetable Physiology at the College de France, and published an outline of his course in 1805, in the Principes de Botanique, prefixed to the Flore Française.

In 1806 he was commissioned by the French government to collect information on botany and the state of agriculture through the whole of the French empire, the limits of which, at that time, extended beyond Hamburgh to the north, and beyond Rome to the south. Every year, during the following six years, he took a long journey in the fulfilment of the task assigned him, and drew up a report of his observations for the minister. In these annual reports, however, he did not confine himself to the special objects of his commission, but made known his views with regard to the internal administrations of the countries he visited; suggesting at the same time measures for their amelioration and for the correction of existing abuses. He had projected a great work on the agricultural state of the empire, and had even executed considerable portions of it, comprehending the “ French Flora,” arranged according to modern views of classification, when the political events of 1814 put an entire stop to the work.

In 1807 he was appointed Professor of Medicine at Montpellier ; and in 1810, a chair of botany was instituted in the same academy, which he was invited to occupy. Under his superintendence, the Botanical Garden of that city was more than doubled in extent, and the study of botany assumed a degree of importance it had never before possessed. De Candolle quitted Montpellier in 1816, very much to the regret of the students and of his colleagues, who employed every means in their power to induce him to remain among them ; but his country had been restored to liberty, and he was firm in his determination to fix himself in his native city, and devote to its services the remainder of his days.

Soon after his return to Geneva he was appointed to the chair of natural history, an office which had been created expressly that he might occupy it. Among the first of the public benefits which he conferred upon his countrymen was the establishment of a botanic garden. The government of Geneva willingly lent their aid in forming so laudable an institution, in which he was also assisted by a great number of voluntary subscribers. The enthusiasm which he inspired for his favourite science was remarkably displayed on one particular occasion, when, being desirous of procuring for Geneva a copy of a Flora of Mexico, which had been deposited with him for a few days, an appeal which he made to the public was responded to with such alacrity, that in the course of eight days one thousand drawings had been finished by amateurs, who volunteered their services on the occasion.

The activity and powers of De Candolle's mind were displayed in a multitude of objects of public utility, the furtherance of which ever called forth in him the most lively interest ;—whether it was the improvement of agriculture, the cultivation of the fine arts, the

advancement of public instruction, the diffusion of education, or the amelioration of the legislative code. Feeling deeply of what vast importance to the welfare of mankind it is that sound principles of political economy should be extensively promulgated and well understood by all ranks of men, De Candolle never failed to develope and enforce those principles in his lectures and popular discourses, as well as in his official agricultural reports. On these subjects, and especially with respect to the immense advantages which would accrue to the community from the unrestricted freedom of commerce, his views were those of the most enlightened policy, and exhibited a sagacity in advance of the times in which he lived.

As a lecturer, he possessed in an eminent degree the power of imparting to his auditors the enthusiasm which glowed within his own breast for the pursuits of natural history. Complete master of the subject of his discourse, his ample stores of knowledge never failed to supply him with illustrations; and even in his extempore effusions, all his ideas were developed in the clearest order, and explained with singular perspicuity.* His chief delight was to afford assistance of every kind to such students as needed it, and in whom he perceived a desire of improvement. His great aim was to inspire and diffuse a taste for the study of botany by rendering it popular among all ranks. His library, which contained the richest collection of works on that subject, and the volumes of his hortus siccus were always open to those who wished to consult them. Often has he been known to discontinue researches which he had commenced on finding that a similar design was entertained by another person ; and he hastened, on these occasions, to communicate to this inquirer his own views on the subject, to place in his hands the materials he had collected, and to put him in possession of the fruits of his own experience. His sole object was the advance of knowledge; and whether this was effected by himself or by others was to him a matter of total indifference.

De Candolle had been visibly declining in health for some years before his end. The sudden death of Cuvier had impressed him with the apprehension that a similar fate might be impending ; and that he himself might, in like manner, be cut off before he had accomplished the great works in which he was then engaged. He, in consequence, resolved to set aside all other occupations, and concentrate all his efforts in completing those more important designs. During the last year of his life he undertook, with the vain hope of improving his strength, a long journey, in the course of which he at

• The substance of De Candolle's popular conrses of lectures on the physiology of plants is contained in - Conversations on Vegetable Physiology, comprehending the Elements of Botany, with their application to Agriculture," by the accomplished authoress of “ Conversations on Chemistry," “ Natural Philosophy," and other well-known works. The first edition appeared in 1829.

tended the scientific meeting held at Turin, where, as might be expected, he met with the most flattering and cordial reception. His death took place on the 9th of September, 1841, in the 64th year of his age.*

Simon L'Huillier, for many years professor of mathematics at Geneva, was born in that city on the 24th of April, 1750. The rapid progress which he made in his collegiate studies was viewed with so much interest by one of his relations, a minister of the reformed church of Geneva, that he bequeathed him a large portion of his fortune, on the express condition that he would embrace the clerical profession ; but young L'Huillier, feeling no inclination to the studies which this condition would have imposed upon him, resisted the temptation, and preferred devoting himself to the pursuits of

* An oration by M. Rigaud, the Syndic of Genera, pronounced at the Conseil Réprésentatif," on the 27th of September, is the source which bas supplied the information here given with regard to De Candolle. The following is a catalogue of such of his works as are in the library of the Royal Society :

1. Essai sur les propriétés médicales des plantes, comparés avec leurs formes extérieures et leur classification naturelle. 8vo, Paris, 1816.

2. Regni vegetabilis systema naturale; sive ordines, genera, et species plantarum secundum methodi naturalis normas ; vol. 1 et 2 : 8vo, Parisiis, 1818 et 1821.

3. Théorie élémentaire de la Botanique, seconde édition, sro, Paris, 1819. (The first edition appeared in 1813.)

4. Prodromus systematis naturalis regni vegetabilis ; sive enumeratio contracta ordinum, generum, specierumque plantarum hucusque cognitarum, juxta methodi naturalis normas digesta : partes I-IV. Bro, Parisiis, 1824 -1830.

5. Mémoire sur la famille des Légumineuses ; 4to, Paris, 1825.

6. Plantes rares du Jardin de Genére ; livraisons I-III ; 4to, Genéve, 1826.

7. Organographie Végétale, on Déscription raisonnée des plantes ; 2 vols. 8vo, Paris, 1827. (This work has been translated into German by Meissner, in 1828.)

8. Collection de mémoires pour servir à l'histoire du Régne Végétal : 1°. Mémoire sur la famille de Mélastomacées ; 2°. Mémoire sur la famille des Crassalacées : 2 vols. 4to, Paris, 1828.

9. Mémoire sur la famille des Ombelliféres ; 4to, Paris, 1829.
10. Mémoire sur la famille des Onagraires ; 4to, Paris, 1829.
11. Mémoire sur la famille des Loranthacées ; 4to, Paris, 1830.
12. Mémoire sur la famille des Valerianées ; 4to, Paris, 1832.

13. Cours de Botanique; seconde partie. Physiologie Végétale pour servir de suite à l’Organographie Végétale, et d'introduction à la Botanique Géo. graphique et Agricole ; vol. i-iii ; 8vo, Paris, 1832.

De Candolle was also the author of an essay on Geographical Botany, prefixed to the second volume of the “ Flora Française" (1805), Of the article “Géographie botanique et agricole,'' in the “ Dictionnaire d’Agricul. ture," published in 1809. Of the article “ Géographie botanique,” in the “ Dictionnaire des Sciences Naturelles," 1820. And of the article “ Phytographie,” in the “ Dictionnaire classique d'histoire naturelle."

(M. De Candolle's Memoir on the genus Brassica was reprinted from the Transactions of the Horticultural Society in Phil. Mag., First Series, vol. Ixi, p. 87.- ED.)

abstract science. The spirit of independence evinced by this sacrifice, together with the extraordinary aptitude he displayed for mathematical acquirements, excited the interest and conciliated the affection of another of his relations, the celebrated Le Sage, by whose instructions and counsels the most salutary influence was exercised over the studies of his pupil. Bertrand, who then occupied the chair of mathematics in the same college, was also one of those who discerned in L'Huillier the dawn of genius; and even at that early period he regarded him as destined to be his successor in that professorship.

As L'Huillier advanced to manhood, it became necessary for him to engage in some active employment, in which he could turn to account his academical attainments. He had the good fortune, at this critical time of his life, to be chosen tutor to Prince Czartorynski, with whom he remained for a period of thirteen or fourteen years; ever honoured with the friendship and respect of all the members of the Prince's family. He dedicated to the father of his pupil his first work, which was published at Warsaw, in 1782, under the title of De relatione mutua capacitatis et terminorum figurarum, geometricè considerata, seu de Maximis et Minimis pars prior elementaris ; in which he treats geometrically, and with singular elegance and vigour of demonstration, all the elementary problems relating to isoperimetric figures and solids. About the same time he presented to the Academy of Berlin a memoir, which was afterwards published in its Transactions, on the minima relating to the figure of the cells of bees, a subject which he appears, in that paper, to have exhausted. *

The prize proposed by the same academy in 1786, was adjudicated to him for a memoir, which was since published under the title of Exposition élémentaire des principes des calculs supérieurs. In this masterly essay the differential calculus is derived from a principle which D'Alembert had, in the first edition of the Encyclopédie, so happily illustrated, and which is now so generally recognised as the basis of that calculus; namely, the doctrine of limits.

On his return to Geneva in 1789, l'Huillier published an opuscle, which acquired great celebrity, entitled La Polygonométrie ; ou de la mesure des figures rectilignes, et abrégé d'isopérimétrie élémentaire, ou de la dépendance mutuelle des grandeurs et des limites des figures ; at the conclusion of which he gives a masterly summary of his former researches on elementary isoperimetry. In this work are given several formulæ of great generality, and which, at that time, were entirely new, and were calculated to facilitate the study of numerous relations arising from the perimeters and areas of polygons. About the same period, indeed, Mascheroni published formulæ very analogous to those of l'Huillier : but the latter afterwards succeeded

[* See Phil. Mag., Second Series, vol. iv, p. 313.-Ev.]

« ZurückWeiter »