102 THE AMERICAN BOTANIST 



tinguished the light of learning in Europe for more than a 

 thousand years. During the Dark Ages as this period was 

 called, such scientific knowledge of earlier days as survived 

 was preserved in monasteries and similar institutions. A 

 knowledge of plants was kept alive hy the necessity for culti- 

 vating food and medicinal plants and passed on from father 

 to son. Occasional books on the subject appeared, but their 

 authors seem to have been chiefly engaged in repeating the 

 statements of the Ancients and in endeavoring to make the 

 plants of their own regions agree with the descri|)tions of 

 Greek plants. 



Toward the end of this period the "doctrine of signa- 

 tures" had a great vogue under the leadership of Bombastus 

 Paracelsus, a Swiss, born the year after Columbus discovered 

 America. Bombastus taught that all plants were created for 

 the good of man and bear upon them signs or "signatures" of 

 their uses. This appealed with special force to a population 

 strongly inclined toward a Ijelief in witchcraft and magic. 

 According to the doctrine of signatures, a plant with red 

 juice is good for the blood, a plant with three-lobed leaves 

 is good for the liver and so on. Some of the common names 

 of plants still bear witness to these curious beliefs as instanced 

 in spleenwort. evebright. heartweed, lungwort, li\erwort, 

 bloodroot. kidne^'wort, and lousewort. 



Other beliefs current when the doctrine of signatures 

 was in repute, still have their adherents in out-of-the-wa}- 

 communities. Divining-rods made from twigs of peach or 

 witch-hazel are still used by the credulous to locate "veins" 

 of water and hidden treasures. And though we no longer 

 believe in the mvstic "fern-seed" that will make one invisi- 

 I)le, in the moonwort that has ])ower to pull the shoes from 

 the newlv shod horse, in the spring-wurzel plant which will 

 open an}' lock it is laid upon, or in the mandrake plant which 



