LEWIS DAVID VON SCHWEINITZ, P. D. 
WITH 
A SKETCH OF HIS SCIENTIFIC LABOURS. 
READ BEFORE 
sit 
THE ACADEMY OF NATURAL SCIENCES OF PHILADELPHIA, 
May 12th, 1835. 
El! 
BY WALTER R. JOHNSON. , 
PUBLISHED BY ORDER OF THE ACADEMY. 
PHILADELPHIA! 
PRINTED BY WILLIAM P. GIBBONS, 
Sixth and Cherry sts. 
1 835 . 
