L A M 



504 



LAM 



proper person to superintend the education of his chil- 

 dren ; and, during lu's residence in the house of the 

 president, at Coire, his thirst for scientific information 

 was amply gratified, by the use of a large and valuable 

 library. Here he accordingly gathered in a store of 

 useful knowledge in various sciences, and learnt seve- 

 ral dead and living languages. Here, too, he began to 

 exhibit some of the fruits of his mathematical attain- 

 ments, by the invention of several machines for facili- 

 tating scientific operations ; such as his mercurial chro- 

 nometer, his arithmetical and logarithmic scales, and 

 his machine for drawing in perspective. About this 

 time, he was admitted a member of a learned society, 

 instituted at Coire ; and he was also elected a member 

 of the Helvetic Society, whose transactions he enriched 

 with a number of mathematical and physical treatises. 

 After a residence of several, years at Coire, he accom- 

 panied his pupils on their travels through a great part 

 of Germany, Holland, and Franee ; and had thus an 

 opportunity of conversing with a number of the most 

 eminent cultivators of science in Europe. In the year 

 1758, he formed an intimate acquaintance with the 

 celebrated philosophical mechanic Brander, at Augs- 

 burgh ; and wrote his Treatise on Photometry, in which 

 he set forth new principles upon this interesting, but 

 hitherto neglected subject. During his residence at 

 Augsburgh, he was chosen a member of the newly es- 

 tablished Bavarian academy of sciences, with a pension; 

 and, at the same time, with permission to reside 

 abroad, provided he contributed to their transactions ; 

 an engagement which he faithfully performed. In the 

 year 1 763, he was appointed one of a commission employ- 

 ed to settle the boundaries between the territories of the 

 Valteline and the duchy of Milan ; and, after the ter- 

 mination of this business, he repaired to Leipsic, where 

 he published his Nnv Organon, a comprehensive sys- 

 tem of logic, containing many original ideas, which 

 procured for its author no small portion of celebrity. 

 At length, on the invitation of the great Frederic of 

 Prussia, who fully appreciated his scientific attainments, 

 he went to reside at Berlin, where he was appointed 

 an ordinary member of the academy, and became a 

 valuable contributor to its transactions. On the esta- 

 blishment of a college, for the purpose of superintend- 

 ing the general improvement of the Prussian state, 

 Lambert was appointed chief councillor for buildings ; 

 which situation he held until his death, on the 25th 

 of September, 1777. 



Lambert was not less esteemed for the amiable quali- 

 ties he displayed in the intercourse of life, than he was 

 respected on account of his scientific acquirements. 

 In his manners and habits, indeed, he exhibited many 

 traces of his originally humble situation in life; but 

 these peculiarities were amply compensated by the ex- 

 cellence of his heart, and his uncommon talents. His 

 morals were correct, and he was impressed with a deep 

 veneration for religious truths. 



If we compare the difficulties with which Lambert 

 had to contend, with the actual extent of his know- 

 ledge, and the success with which he prosecuted his 

 scientific researches ; he must undoubtedly appear to 

 have been a man of no ordinary genius. Of him, it 

 may be said with truth, that he derived his knowledge 

 more from the resources of his own mind, than from 

 books; and, hence, he always places the subject of 

 which he treats, in a new and original point of view. 

 The sciences of logic, metaphysics, and mathematics, 

 were those which he chiefly cultivated. In the two 



Lamp. 



former sciences, as may be seen from his New Organon, Lambert 

 and his Architectonic, he endeavoured to investigate 

 our simple notions, as the Basis of all philosophical 

 knowledge, with the same acuteness and precision as 

 the notion of quantity is treated in mathematics. The 

 various branches of mathematical and physical science, 

 are eminently indebted to the researches of this philo- 

 sopher ; and his treatises on Practical Geometry, Sphe- 

 rical Trigonometry, Optics, Astronomy, Sfc. may be 

 studied with advantage, even in the present more ad 

 vanced state of the sciences, which he proposed to il- 

 lustrate or extend. 



The following list, we believe, will be found to com 

 prehend all his most important publications.. 



Photometria, s. de mensura et gradibus luminis, colo* 

 rumelumbrce. Augsburgh, 1760. 8vo. This work is 

 very scarce. Kosmologische Briefe. Ibid. 1761. 8vo. 

 Insigniores orbita; Cometarum proprielates. Ibid. 1761. 

 8vo. Neues Organon. Leipsic, 176*. 2 vols. 8vo. Bey- 

 Iragc zum Gebrauc/i dcr Mathematik. Berlin, 1765- 

 1772. 3 vols. 8vo. ArchilektoiM. Riga, 1771. 2 vols. 

 8vo. Freye Perspectio. Zurich, 1759- 8vo. Second Edi- 

 tion, 1774. 2 vols. 8vo. Hygomelrie. Augsburgh, 1774. 

 8vo. 



The " Berliner Ephimersden," an astronomical jour- 

 nal, on the plan of the Parisian Connoissance des Temps, 

 was originally undertaken at the suggestion of Lam- 

 bert. 



LAMBETH. See SURREY. 



LAMP is a well known apparatus, for producing ar- 

 tificial light. 



A lamp, in the most simple form, has a wick, com- 

 posed of several cotton threads, partially immersed in 

 oil, contained in a flat dish, furnished with some small 

 support, to hold the upper end of the wick in a per- 

 pendicular direction, a small height above the surface 

 of the oil; this oil-holder, or dish, when suspended in 

 a globular glass-case, is the common street lamp. When 

 the wick is lighted, by the application of a burning 

 torch, the heat of its flame causes the oil, which is 

 contained in the wick, to boil, or rise in vapour ; and 

 the combustion of this vapour, is the flame which pro- 

 duces the light. As fast as the oil in the wick is carried 

 off, by this vaporization, a fresh supply is drawn up, 

 by the capillary attraction of the wick, from the oil con- 

 tained in the oil-holder. 



Hence it appears, that lamps *nd candles, are both 

 of the same nature as gas-lights. The difference con- 

 sists in the materials from which the gass is to be ex- 

 tracted, and the manner in which the extracting of 

 it is performed; but in all cases, flame is nothing 

 more than the combustion of gas. In gas lights, an 

 apparatus is previously employed, to make and pre- 

 serve the gas, and to conduct it to the place where ar. 

 tificial light is to be obtained from its combustion ; but 

 in lamps and candles, the heat of the same flame, which 

 produces the light, is employed to vaporize the cqm- 

 bustible matter, and form gas for its own maintenance. 

 The difference between lamps and candles is, that 

 lamps are supplied with the combustible matter in a 

 fluid state, but candles are supplied with a solid mate- 

 rial ; and the heat of the flame must first be employed, 

 to reduce the tallow or wax to a fluid state; and this 

 fluid, which forms itself round the base of this wick, 

 sustains the flame just in the same manner as the oil in 

 lamps. The process of burning in candles, has been ex- 

 plained in our article CANDLE, vol. v. p. 375 ; but, as 

 the combustion is more perfect in well constructed 



