422 



T. VOKOI. 



From the existing literature on the subject, it may be concluded 

 that tlie quantity of nutriment contained in a seed has no intimate 

 relation to its specific gravity. So far as specific gravity of the 

 constituents of seed alone is concerned, it is not without reason to 

 infer that those seeds which are rich in mineral matter have a 

 higher specific gravity ; that those rich in starch have a higher 

 specific gravity than those rich in albuminoids and those rich in oil 

 lighter than those rich in albuminoids. But there is still another 

 constituent or rather accidental ingredient having a much lower 

 specific gravity than even oil, viz. free air. The specific gravities 

 of the various constituents of seeds may be seen from the following 

 table^^':— 



Starch 1. 479-1. 630 



I'alm staixh I-450 



Cellulose i. 25-1. 45 



*Lignose 1.460-1.534 



Plant mucilage i. 300-1. 600 



Cane sugar i .404- 1 .606 



Gluten of wheat pulv 1-297 



Gluten air dried i .036 



Legumin pulv i .360 



I^gumin, compact 1.285 



Wax 0.941-0.999 



Resin 0.9-5-I.22& 



Fat 0.892-0.999 



Etherial oils 0.740 -1. 140 



Extractive matter about 1.^00 



Ash constituents about 2.5 



Atmospheric air 0.001293 



Carbonic acid 0.001978 



Nitrogen .... 0.001267 



Oxygen 0.001432 



Water i .00 



As there is no seed which does not contain more or less free 

 air, and as the quantity of air contained must be variable with the 

 number and size of the cavities and spaces within, the quantity of 

 air contained must be, within certain limits, the principal or the 

 most influential factor in. determining the specific gravity of seeds. 

 Thus it naturally follows that seed containing larger c[uantity of 

 starch may be lower in specific gravity than one rich in albuminoids, 

 as can be seen in the case of " mealy " and "glassy" sorts of cereals. 

 Indeed when we carefully examine the tables of analj'sis we see 

 that the relation between the percentage of the various constituents 

 and the specific gravity of a seed is rather irregular, and even with 

 seeds having almost the same weight the one containing more 

 nutriments is not necessarily the one having a greater specific 

 gravity ; nor do those having a higher specific gravity necessarily 

 contain more mineral matter and less nutriment. 



(3) ii u z, Lmdwirth. Samcnkunde pp. 243 Vol. I, 1885, Berlin. 



* According to Rumford the lower figure here given represents the siiccilic gravity of 

 the oak, and the higher, that of the maple. 



