THE point raised by Mr. Cumming in last week's NATURE (vol. xxxvii. p. 584), as to the use of the words density and specific gravity is, it seems to me, of some importance. For many years past I have, ...

IN the course of some work on lapis lazuli, we were astonished to find how wide was the discrepancy between the specific gravities of our specimens and the values accorded to this rock by all the ...

Germination and vigor problems in sorghum are usually related to weathering during the post-maturation, pre-harvest period and to drought induced seed immaturity. Weathering and immaturity also lowers ...