141 



answered in favour of the Sisal growers prospects ; a fact which is much 

 to be regretted. Sir Ambrose Shea expressed the opinion that Trinidad 

 would not be able to enter the competition, but it has since been fully 

 proved, not only that Sisal can be grown in Trinidad, but that the 

 fibre produced is superior to the produce of the Bahamas, showing 

 that his opinion rested upon no foundation and that he was certainly 

 uninformed of the conditions which existed in this Island. If ever 

 the circumstances arise which will make Sisal Hemp a paying industry 

 in the Bahamas, it may also be relied upon as certain, that it will pay 

 to as large an extent when grown in suitable lands in the Island of 

 Trinidad, which has moreover many advantages not possessed by the 

 Bahama Islands. 



Note. — Since the above was written Dr. Morris of Kew has visited the 

 Bahamas and is of opinion that Sisal has a fair future before it there. 



178.-NOTES ON MANURING. 



The following notes were originally printed in "Garden and 

 Field" a South Australian Publication, under control of the Depart- 

 ment for Agriculture of that Colony. They were reprinted by the 

 Editor of the Agricultural Journal of the Cape of Good Hope of 

 August, 1895 :— 



VfOKT^lES OIKT IlVIfA. »r XT IS I M^ O . • 



By Professor Laurie, M.A., B.Sc. 

 (Cape AgriculUiral Journal.) 



Sources of Plant Food. 



The elements or substances which plants use in building themselves are 

 derived from the air, the rain, and the soil. From the air and the rain 93 per 

 cent, fully of their total substance is obtained, and the remaining 6 or 7 per cent. 

 is taken up through the agency of the roots from the soil. 



Action of the Leaves. 



Carbon. — From the air, for example, carbon, which enters into the composi- 

 tion of all plants to the extent of 40 to 48 per cent, of their weight, is obtained 

 through the agency chiefly of the leaves from the carbon dioxide, which ia 

 present in very small proportion in the atmosphere. The leaves absorb the car- 

 bon dioxide, and in the cells constituting their tissues under the action of sun- 

 light it is decomposed into its two constituent elements, carbon and oxygen. 

 The carbon is retained and used in the elaboration of the various substances of 

 their tissues, and the oxygen is exhaled. 



Action of the Roots. 



Nitrogen and Mineral Matter. — While this assimilation is going on the roots 

 supply their complement by absorbing through delicate root hairs and otherwise 

 nitrogen as nitrates, mineral matter, and water in a more or less complex solu- 

 tion. The following substances are taken up this way in solution in more or less 

 complex combination : — Nitrogen, phosphoric acid, potash, lime, magnesia, iron, 

 sulphuric acid, soda, chlorine, silica, manganese, with one or more rarer sub- 

 stances m some particular plants. 



*Oarden & Field. 



