2 5 6 THE POPULAR SCIENCE MONTHLY. 



SKETCH OF MATTHIAS JACOB SCHLEIDEN. 



" rjlWO names," says M. Leo Herrera, in the " Revue Scientifique," 



JL " are inseparably connected with that grand movement of the 

 biological sciences that began about 1838, and of which we to-day 

 contemplate the superb bloom Schleiden and Schwann. The two 

 laid the foundations of the cellular theory. Both exercised a power- 

 ful influence over their contemporaries ; both rendered lasting services 

 to science through their teaching, their pupils, their ideas, and even 

 through their errors." 



Schleiden devoted himself variously to law, medicine, the natural 

 sciences, and philosophy, and his works bear the marks of those diver- 

 sified studies : but he was, above all, a botanist ; it was under this 

 title that he became famous, and by this his name must endure. 



Matthias Jacob Schleiden was the son of the physicist, Andreas 

 Benedict Schleiden, and was born in Hamburg, April 5, 1804. On 

 quitting the gymnasium he entered upon the study of the law at 

 Heidelberg in 1824. He received his degree in 1827, and had entered 

 upon the practice of his profession in his native city, when, in 1831, 

 he concluded that the natural sciences were more to his taste than the 

 law. With the encouragement of his father, he returned to the uni- 

 versity, and studied medicine at Gottingen where he enjoyed the 

 instructions of Bartling in botany and the natural sciences at Berlin, 

 where his uncle, the botanist Horkel, enlisted his special interest in 

 that branch. In 1839 he was appointed, on the recommendation of 

 Humboldt it is said, Adjunct Professor of Botany at Jena, where he 

 continued to teach in the chair of that science till 18G2. 



Schleiden was thirty -three years old when he published his first 

 works ; the scientific collections from 1837 to 1852 contain twenty- 

 seven memoirs contributed by him. The most striking of these essays 

 and the ones which contributed most directly to his rapid rise to 

 eminence, were those in which he propounded his theories of the 

 origin of plant-cells and of fructification. These were the " Beitrage 

 zu Phytogenesis " ("Contributions to Phytogenesis," 1838), and 

 " Ueber Bildung des Eichens und Entstehung des Embryos beim Pha- 

 nerogamen " (" On Formation of the Ovule and Origin of the Embryo 

 in Phanerogams," 1839) his "most remarkable, most revolutionary, 

 and most erroneous works," which astonished the world, "just as 

 he had barely made himself known by a few anatomical and organo- 

 genical researches." Both of these works called forth lively re- 

 sponses. They were translated into English and French. They were 

 commented upon and discussed, and were the subject of passionate 

 debates ; in short, inquiry was awakened, and an impulse was given 

 to investigation, the force of which has not slackened to this day. 



