LIGNUM NEPHRITICUM—YTS HISTOEY AND AN AC- 

 COUNT OF THE EEMARKABLE FLUORESCENCE OF 

 ITS INFUSION.^ 



By W. E. Saffoed, 

 Economic Botanist, U. S. Department of Agriculture. 



[With 7 plates.] 

 INTRODUCTION. 



LignuTTi nephriticum is a remarkable wood which was celebrated 

 throughout Europe in the sixteenth, seventeenth, and the early part 

 of the eighteenth centuries, not only for its reputed medicinal virtues 

 but on account of the strange color phenomena displayed by its 

 infusion in spring water. Cups turned from it were deemed fit gifts 

 for emperors and princes. The water drunk from these cups, or 

 from bowls in which a few chips were allowed to remain, was 

 declared to work marvellous cures; and its beautiful opalescence 

 and changes in sunlight and shadow were the subject of investiga- 

 tions by the most celebrated physicists of that period. Strange to 

 say, scarcely a fragment of this wood is now to be found in museums 

 or drug collections. Its very name has disappeared from modern 

 pharmacographies and encyclopedias; and its botanical identity has 

 remained doubtful until the present day. In the present paper I 

 propose to show that this classic wood came from tAvo distinct 

 sources, from trees of distinct genera. I shall also give an account 

 of the fluorescence of their extracts, and endeavor to explain the 

 causes which led to the confusion of their identity. 



EARLY HISTORY. 



The Spanish physician Monardes was the first to call attention 

 to the wood. In 1565 he wrote the following account of it : 



They also bring from New Spain a wood resembling that of a pear tree, 

 dense and without knots, which they have been using for many years in these 

 parts for diseases of the kidneys and of the liver. The first person I saw use 

 it was a pilot, 25 years ago, who was afflicted with urinary and kidney trouble, 

 and who after using it recovered his health and was very well. Since then 



1 Based upon a paper entitled " The Rediscovery of Lignum nephriticum," read by the 

 author Feb. 2, 1915, at a meeting of the Botanical Society of Washington. Published by 

 authority of the Secretary of Agriculture. 



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