174 POPULAR SCIENCE MONTHLY. 



shown in the view of the Botanical Laboratory exhibits the 

 formal style of planting which prevailed in earlier times. 



The Chelsea garden is situated near the Thames, about two 

 miles south from Hyde Park. It was formed by the Apotheca- 

 ries' Guild of London, for the growth of plants for commercial 

 purposes. Later it was converted to its present use, that of 

 furnishing material to illustrate lectures in pharmacy and medi- 

 cine. Surrounded on all sides by brick buildings, and shaded 

 by smoke and fog, the rectangular plots of officinal plants ex- 

 hibit very strikingly the deleterious effects of an atmosphere 

 laden with acids. The would-be visitor to this quaint old place 

 must arm himself with an admission card obtained from the 

 Apothecaries' Society, and from the creaking formalities attend- 

 ant upon the granting of such permission by unaccustomed but 

 polite officials it may be inferred that the casual sight-seer does 

 not often find his way into the place. 



During the period inclusive of the foundation of the last-named 

 institutions plants began, however, to be considered from another 

 point of view from a strictly scientific standpoint, and as inde- 

 pendent organisms. While the Aristotelian school studied plants 

 in a manner closely approaching that of the present time, yet this 

 beginning of biological science had no logical continuation, and 

 during many succeeding centuries was completely lost to sight. 

 In the latter half of the sixteenth century two new forces were 

 manifest in the development of these institutions. Many of the 

 wealthier class who had private gardens began to enlarge them 

 by the addition of species because of their rarity, or because they 

 were brought from some foreign country, and in many instances 

 special collections were made chiefly for this purpose alone. Thus 

 it may be seen that beyond the useful properties of plants, per- 

 haps the first truly scientific idea of them concerned in a crude 

 way some of the principles of geographical distribution. This 

 phase of the subject received an increasing attention, and finally 

 assumed form and order upon the introduction of the Linn?ean sys- 

 tem of classification into Germany and that of Jussieu into France. 



Before this, however, a still more important development in 

 the method of study of plants had ensued, as is shown distinctly 

 in the botanical writings of the latter half of the sixteenth cen- 

 tury. The all-important fact of the natural affinities of plants 

 had gradually assumed distinctness an idea not within the 

 grasp of any one of the herbalists of the time, whose accumulat- 

 ing and repeated descriptions of individual species gave rise to 

 the perception of resemblance and difference in forms, and finally 

 to the idea of natural relationship. This idea finally became para- 

 mount : " All the foreign matter introduced into the descriptions 

 of plants by medical superstition and practical considerations 



