*rke Principles, of Part V. 



grow when it paffcs the age of five years : 

 but the time cannot be precifely fixed, for 

 that muft depend on the drinefs and oili- 

 nefs of the feeds. All the oily feeds keep 

 long, fome of which will lie in the earth 

 for fifteen or twenty years. Two months 

 after the great fire in London there ap- 

 peared a great crop of a Ipecies of eryfi- 

 mum> where there had been houfes for a 

 thoufand years. Mr. Reaumur fbwed fome 

 of the grain which had been preferved in 

 the citadel of Metz for one hundred and 

 thirty years; and which made very good 

 bread. In three weeks fome of the grains 

 were fwelled, and fome not. In fix weeks 

 no grains were to be found. 



THE caufe of ilerility in old grains feems 

 to confift in the vefiels lofing that fupple- 

 nefs which is neceffary for their extenfion, 

 and filling with water; and in the con- 

 tained liquor lofing that gluinefs which is 

 neceflary for nutrition. This appears from 

 the brittlenefs of the grain, which becomes 



fo 



