178 



Analyses of Ashes of Plants, 



There are other circumstances which must influence this re- 

 sult. The point of perfect maturity in a root crop cannot be 

 defined so distinctly as that of a grain crop ; and it may well be 

 believed that as soon as a plant has reached this point, changes 

 will occur to modify extremely the nature of the mineral matter. 

 Some of these may be thrown back into the soil, and a difference 

 of a week in the age of the plant may alter materially the results 

 of the analysis. This question can only be fully enlightened by 

 the examination of specimens periodically ; every week or fort- 

 night, that is, of their growth. We have long felt the necessity 

 of this plan, which has been ably advocated by Professor John- 

 stone in the last edition of his valuable treatise ; but we think it 

 of more importance at present to limit our inquiry to the general 

 rather than particular subjects which are connected with the in- 

 organic constitution of vegetables. The composition of the ash 

 of different specimens of turnips will be best seen if we give in a 

 table the analyses before detailed : — 



Table 4. — Composition (in 100 parts) of the Ash of Turnip Bulbs. 



No. of Spec. 



82 



83 



84 



85 



77 



86 



Mean 

 of the six " 

 Sijecimens. 



Variety. 



Skirving's 

 Swede. 



Skirving's 

 Swede. 



Dale's 

 Hybrid. 



Dale's 

 Hybrid. 



Skirving's 

 Swede. 



Green-top 

 White, 



Per Centagel 

 of Ash . / 



•75 



•76 



1-09 



•725 



•88 



•592 





Silica . . 

 Phosph. Ac. 

 Sulph. Ac. 

 Carb. Ac. . 

 Lime . • 

 Magnesia . 

 Perox. Iron 

 Potash . . 

 Soda . 

 Chlo. Sodium 

 Chlo. Potass. 



Total , 



2- 69 

 9-31 



16-13 

 10'74 

 11-82 



3- 28 

 -47 



23-70 

 14-75 

 7-05 



1- 73 



10- 17 

 15-53 



11- 96 

 r4-3§ 



3-27 

 •61 

 26-88 

 13-31 



2- 19 



2-75 

 8-77 



11- 71 



12- 66 

 6-46 

 2-51 



•14 

 36-93 

 8-01 

 10-00 



1-12 



10- 71 



11- 22 



12- 05 

 8-87 

 1-93 



•63 

 32^39 

 6^71 

 14-30 



1- 63 

 12^51 

 11-26 



9-54 

 11-36 



2- 44 

 •28 



36-16 

 4-99 

 9-77 



•96 

 7-65 

 12-86 

 14-82 

 6-73 

 2-26 

 -66 

 48-56 



5-44 



1- 81 

 9-85 



13-12 

 11-96 

 9-93 



2- 61 

 •46 



34-10 



7- 96 



8- 13 



99-93 



99-98 



99-94 



99-93 



99-94 



99-94 



99-93 



