yii PREFACE. 



The Natural System of Botany being founded on these principles, 

 that all points of resemblance between the various parts, pro- 

 perties, and qualities of plants shall be taken into consideration; 

 that thence an arrangement shall be deduced in which plants must 

 be placed next each other which have the greatest degree of simi- 

 larity in those respects; and that consequently the quality of an im- 

 perfectly known plant may be judged of by that of another which 

 is well known, it must be obvious that such a method possesses 

 great superiority over artificial systems, like that of Linnaeus, in 

 which there is no combination of ideas, but which are mere collec- 

 tions of isolated facts, having no distinct relation to each other. 

 The advantages of the Natui'al System, in appljdng Botany to use- 

 ful purposes, are immense, especially to medical men, who depend 

 so much upon the vegetable kingdom for their remedial agents. A 

 knowledge of the properties of one plant enables the practitioner 

 to judge scientifically of the qualities of other plants naturally allied 

 to it ; and therefore, the physician acquainted with the Natural 

 System of Botany, may direct his inquiries, when on foreign 

 stations, not empirically, but upon fixed principles, into the quali- 

 ties of the medicinal plants which have been provided in every 

 region for the alleviation of the maladies pecuHar to it. He is 

 thus enabled to read the hidden characters with which Nature 

 has labelled all the hosts of species that spring from her teeming 

 bosom. Every one of these bears inscribed upon it the uses to 

 which it may be applied, the dangers to be apprehended from it, 

 or the virtues with which it has been endowed. The language 

 in which they are written is not indeed human ; it is in 

 the living hieroglyphics of the Almighty, which the skill of man 

 is permitted to interpret. The key to their meaning lies enveloped 

 in the folds of the Natural System, and is to be found in no other 

 place. 



The great obstacle to the adoption of the Natural System of 

 Botany in this country was the supposed difiiculty of mastering its 

 details ; but of that difficulty it may be observed, in the first 

 place, that it is only such as it is always necessary to encounter 

 in all branches of human knowledge; and secondly, that it has 

 been much exaggerated by persons who have written upon the 

 subject without understanding it. 



It has been pretended that the characters of the Natui-al classes 

 of plants are not to be ascertained without much laborious research ; 

 and that not a step can be taken until this preliminary difficulty 



