2 BULLETIN 452, U. S. DEPARTMENT OF AGRICULTURE. 
rotundifolia grapes from North Carolina. In New Jersey the terri- 
tory about Vineland and Egg Harbor was fairly well covered, and 
representative samples were collected and sent to the food and drug 
inspection laboratory at Philadelphia, where they were analyzed. 
In New York the region about Keuka Lake was covered and 
representative samples of table and wine grapes were collected 
and sent to the food and drug inspection laboratory at Buffalo, 
where they were analyzed. Further collections in New York were 
made of the Concord variety from the Chautauqua district. In this 
district and the adjacent northwestern part of Pennsylvania are lo- 
cated the largest grape-juice factories in the world; they use only 
Concord grapes for making grape juice. 
During this investigation samples of every variety of grapes found 
in cultivation in the territory covered have been taken purposely 
because the available data on the composition of American native . 
grapes were very inadequate. 
Up to the present time, of the many varieties of grapes put out by 
the plant propagators, only a few have proved sufficiently valuable 
to warrant extensive cultivation. Yet it is important in a general 
investigation to make a fairly complete examination of all varieties 
found in cultivation until sufficient information as to their compo- 
sition is available from which to obtain a basis for more discriminating 
work. 
COLLECTION OF SAMPLES. 
The sampling in 1911 was done almost wholly by persons employed 
temporarily by the Bureau of Chemistry and in a few instances by 
volunteer assistants. These assistants lived in the locality where 
the samples were taken and were engaged for this work because 
of their knowledge of the varieties. Every precaution was taken 
to secure samples which represented the average of the crop. The 
preparation and treatment of the samples during analysis were the 
same as described in Bulletin 145.” 
The sampling in New Jersey and in the Keuka district in New York 
in 1913 was done by a member of the Bureau of Chemistry who 
personally visited the growers and collected samples of ripe fruit 
typical of each variety and crop.. The samples reached the labora- 
tory in good condition in both cases. 
The sampling of Concord grapes in the Chautauqua district in 1913 
was done at one of the large grape-juice factories. Certain crops were 
sampled six times between October 10 and 21 and in each case average 
fruit was taken. Care was observed to select crops which repre- 
sented the different soil formations of the district. Eight crops were 
sampled on each date and in every instance a composite of these 
2 Ibid, pp. 9-11. 
