220 THE BOTANISTS OF PHILADELPHIA. 



ISAAC BURK. 



Isaac Burk, one of the best informed of local Phila- 

 delphia botanists, was born at Aston, Delaware County, 

 September 1, 1816. He removed to Philadelphia in 1838, 

 where he opened a merchant-tailor shop on Spruce Street, 

 below Sixth. He also had a store on Coates Street, now 

 Fairmount Avenue. Having very poor health, he was 

 advised by his physician to seek out-door employment, and 

 heeding his physician's advice, he purchased a Ledger route, 

 which he held for thirty years. He was a student of botany 

 from his boyhood, and his love for the science did not 

 desert him in manhood, for all of his leisure time was spent 

 in making collections of plants and in the study of natural 

 history in general. He helped to classify and arrange the 

 plants in the collection of the Academy of Natural Sciences, 

 of which he was a life member. In 1880 he presented his 

 entire herbarium, which represented so many years of toil 

 and collection, to the Biological Department of the Uni- 

 versity of Pennsylvania, where it is carefully maintained as 

 a special collection especially rich in local and introduced 

 plants. The ballast plants, to which Mr. Burk gave so 

 much attention, are especially well represented. Mr. Burk 

 was, in several cases, the first botanist to report the intro- 

 duction of weeds to this country, which have since become 

 so widely distributed. It is to this side of his botanical work 

 that we must look for the most valuable results achieved for 

 science. He was familiar with the literature relating to 

 plants, and was the author of a series of articles on the 

 Flora of Fairmount Park, which appeared in the Public 

 Ledger of Philadelphia, prior to the Centennial year. 

 Several articles from his pen were published in the 



