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twenty-eight bronze tablets and the fastening of them to as many 
boulders in the Botanic Garden. 
The great diversity in the composition and sources of these 
boulders is emphasized by the fact that, of these twenty-eight, six- 
teen are of unlike composition and their sources are even more 
Fic. 22. Boulder of Pegmatite, in the Rock Garden. (Number 10 of 
abeled boulders.) To illustrate the bronze tablets. (7992) 
— 
the 
diverse. The shortest journey traveled appears to be that of the 
white marble boulder, No. 15, which came from the northern part 
of Manhattan Island (Inwood) or from Spuyten Duyvil, just 
~ 
across the Harlem River—approximately 15 miles. The longest 
journey is that of the Syenite-Granite boulder, No. 23, which was 
brought by the glacial ice from the southeastern Adirondack 
