K A E 



Kaeitnci. which, however, he soon afterwards relinquished, in 

 v ' order to visit other distant countries. With this view, 

 he went on board the Dutch fleet, which was then 

 cruising in the Persian Gulf, as a naval surgeon ; and 

 after visiting a number of the English and Dutch set- 

 tlements, he came to Batayia in lO'Sy. In the follow- 

 ing year, he went, as physician to the embassy of the 

 Dutcli East India Company, to Japan, where he re- 

 mained more than a year. In the beginning of 1692, 

 he set out on his return to Europe ; obtained the de- 

 gree of Doctor of Physic at Leyden, in l60t ; and then 

 returned to his native country, where he was appoint- 

 ed physician to the Count Frederick Adolphus of 

 Lippc. 



During the course of his extensive travels, Kaempfer, 

 actuated by an insatiable curiosity, had studied with 

 grivit attention the natural. and political history, man- 

 ners, and customs of the different countries which he 

 visited ; and brought home complete journals, draw- 

 ings, and various curiosities. He now began to digest 

 his materials, and to communicate his discoveries to 

 the public, in a work entitled, Amcenitates exotica po- 

 litico-medico;, Lemgo, 1712, in 4-to. of which, however, 

 only five fasciculi appeared, with_plates. At his death, 

 which took place in November 1716, he left behind 

 him a great mass of manuscripts and drawings, and 

 particularly an History and Description of Japan. 

 These treasures were purchased by Sir Hans Sloane, 

 who caused a translation to be executed of the work 

 upon Japan, which appeared at London in 1727, in 

 two volumes 4to. A copy of the German manuscript 

 of this book was afterwards discovered at Lemgo, and 

 published by Kaempfer's countryman, Dohm, in the 

 years 1777 and 1779, in two volumes 4-to, with many 

 additions. 



The extensive knowledge, acute observation, and 

 love of truth, which are displayed in the works of 

 Kaempfer, have acquired for their author a considera- 

 ble portion of celebrity. These works consist of his 

 History of Japan; the Amcenitates exotica; an Herba- 

 rium Ultra-Gangeticum; a dissertation de Magislatis 

 divisione, and his Inaugural Theses, on taking his de- 

 gree at Leyden. 



KAESTNER, ABRAHAM GOTTHELF, an eminent 

 German mathematician, was born at Leipsic, on the 

 27th of Sept. 1719. His instruction had been con- 

 ducted privately, under the direction of his father, and 

 some of his other relations, with so much success, that 

 in his tenth year, he was enabled to attend his father's 

 lectures ; and, at the age of twelve, he became a regu- 

 lar student at the university. At that period, his at- 



410 K A E 



tention was principally directed to the study of juris- Kaestner. 

 prudence, although, by his own account, he had a **^~Y~ m ~' 

 great predilection for philosophy and the mathematics. 

 His diligence was so great, and his p>ogress so rapid, 

 that, in his sixteenth year, he became qualified for the 

 degree of Bachelor in Law ; and, at eighteen, he took 

 the degree of Master in the philosophical faculty. Soon 

 after, he commenced his career as an academical teacher, 

 and deli rered private lectures for seven years; when he 

 was appointed an extraordinary professor of the mathe- 

 matics, in 1746. In 1756, he succeeded Segner, as or- 

 dinary professor of natural philosophy and the mathe- 

 matics at Gottingen. He obtained the title of aulic 

 counsellor in 1765, and continued in this situation du- 

 ring four and forty years, until the period of his death, 

 on the 20th of June, 1SOO. 



Kaestner's greatest merit consisted in a happy talent 

 for exhibiting the principles of mathematical science in 

 a luminous and intelligible form. His " Elements of 

 Arithmetic," and other elementary treatises on different 

 branches of the mathematics, are extremely valuable. 

 Their merit was so conspicuous, that they gradually, 

 almost entirely superseded the compendia of the cele- 

 brated Wolf, which had previously been universally 

 adopted in the German universities ; and contributed 

 greatly to facilitate and diffuse the study of mathemati- 

 cal science. His separate treatises are distinguished 

 by the same acuteness of thought, and perspicuity of 

 arrangement. Among these we shall only mention his 

 " Observations on Mining, nilh an introduction to the 

 method of measuring heights by means of the barome- 

 ter," which was published in 1775. Kaestner also 

 translated several works from other languages into 

 German ; such as Hallot's Art of Dyeing, Smith's 

 Optics, and Lulof's Introduction to the Knowledge of 

 the Globe. The Transactions of the Royal Swedish 

 Academy of Sciences were partly translated by him, 

 and partly by others under his inspection. 



Kaestner, however, did not confine himself within 

 the province of the mathematics, but frequently dis- 

 played his talents in other departments of literature. 

 He particularly distinguished himself as an epigram- 

 matist, and made himself both esteemed and dread- 

 ed by the sallies of his wit; in which he is thought to 

 have sometimes been too fond of indulging himself. 



His last great work, the " History of the Mathema- 

 tics," published at Gottingen, 1795-1800, in four vo- 

 lumes, although valuable as an index to the literature 

 of the science, betrays evident marks of the age and 

 declining talents of the author. 



Kaleido- 

 scope. 



PLATE 

 CCCXLI. 

 Kig. 1. 



KALEIDOSCOPE. 



K.ALEIDOSCOPE * is the name of a new instrument, in- 

 vented by Dr. Brewster, for the purpose of creating and 

 exhibiting an infinite variety of beautiful and perfectly 

 symmetrical forms, and is derived from the Greek words 

 xaAej, beautiful, j3 ?) a form, and <nt<ws, to see. 



This instrument in its simplest form, consists of two 

 reflecting surfaces, as shewn in Fig. 1, placed be- 



tween the eye and certain objects, by the combination 

 -of which the picture is to be created ; but as the reflec- 

 tors may have an infinite number of positions with re- 

 spect to each other, as the eye may have an infinite 

 number of positions with respect to the common section 

 of the two planes, and as the object may also have an 

 infinite number of positions with respect to the reflectors, 



The word Kaleidoscope has been preferred to Callidoscope, Calidoscope, and Caleidoscopc, not merely becauss it approaches nearer to the 

 original words of which it is compounded, but to avoid the appearance of its being derived from the I^arin words callidus or callilus. There 

 arc tevcral technical words derived from the Greek, where the K is not changed into C, such as Keratoj>!,ytoti, Kcninhi, &c. which are 

 derived from xi{ 5 , a horn, and several also, in which the word */<>$ does not double the L in its compounds, 



Kaleido- 

 scope. 



