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to the soil on which they grow. The only small fruits which require special fertilizers is 

 the strawberry, which does best by a treatment of bone-dust and ashes, or phosphates. 

 The ordinary barn-yard manure, being apt, especially if too largely applied, to make the 

 plant run to leaf instead of fruit. 



I have indicated above that the manure should be suited to the soil, as much as to 

 the plant grown upon it, and as this is one of the fundamental principles of vegetable 

 growth, a few remarks on the treatment of soils, and on plant life, may be more interest- 

 ing than a disquisition of special fertilizers. 



I believe the discovery of the remarkable power of the absorption possessed by 

 arable, that is cultivated soils, is generally attributed to Bai-on Liebig, the great modem 

 German agricultural chemist. It is now demonstrated that the food of plants cannot ex- 

 ist for any length of time in solution in the earth. It is therefore certain that there can- 

 not be a circulation of such solution towards the roots, these must go in search of food. 

 Hence it is necessary, if it is wished to arrive at an adequate idea of the requirements of 

 plants in the shape of nutriments, to study the growth and ramification of their roots. 



If therefore the food of plants is not held in solution in the ground it will easily be 

 seen that those portions of the soil traversed by the numerous rootlets will, to a certain 

 extent, be exhausted of its plant-sustaining elements, whilst the immediate adjacent por- 

 tions, where no roots have penetrated, are rich in them. Should it be necessary to grow 

 a succeeding crop of equal value in all parts of the same field, it will be necessary to 

 mix the exhausted and unexhausted particles of the soil by mechanical means, and to 

 add certain manures or other chemical compounds, to supply what has been removed by 

 previous crops. In order to do this properly it is necessary for the cultivator to under- 

 stand the nature of his soil and sub-soil. 



In the upper surface of the soil are found all the required elements for the produc- 

 tion of plants to supply the wants of man and the animals that subsist on them. These 

 elements are accumulated by the absorptive power of soils, and it is this absorptive power 

 which removes from solution the soluble salts required for the fertility of the soil. For 

 instance, it is well-known that charcoal, as an absorbent, is used in most filters, and in the 

 same way animal charcoal is employed by the sugar refiners. Arable soil is found to pos- 

 sess the same properties, though in a less degree. Diluted liquid manure of a deep brown 

 colour and strong smell, if passed through arable soil, will be found to flow ofi" both 

 colourless and inodorous. Not only does it lose its smell and colour, but the ammonia, 

 potash, and phosphoric acids which were held in solution are almost, if notquite withdrawn. 



The fertile particles which are attracted to the soil through which they were passed 

 with the fluid in which they were held in solution, is that upon which all plants feed. I may 

 remark, that in using the word attraction, it is perhaps best to explain that it is not used 

 to mean that sort of attraction which causes the needle of a compass to point to the north, 

 but merely a chemical afiinity which the soil has for particles which form food for plants. 



It is by the vital process of vegetation that the stems and leaves of plants are formed 

 by the food the plant feeds upon. All the foods for the support of plant life are formed 

 in the mineral kingdom. The cosmical conditions of vegetable life are heat and sunlight. 

 The gaseous elements which are absorbed by the leaves of plants are in continual motion 

 in the air. The co-operation of the cosmic and chemical conditions, form the perfect 

 plant. I merely make these brief remarks on the action of manures on soils and the 

 growth of plants, so that some idea may be had as to the way plants are acted upon by 

 artificial stimulants which are given to the soil by the cultivator. In a paper of this 

 nature I must necessarily be brief, as it would take up too much time to point out the at- 

 tractive force of different soils. It may be laid down as an axiom, that the power of a 

 soil to nourish cultivated plants is in exact proportion to the quantity of nutritive sub- 

 stances which it contains in a state of physical saturation ; but all soils will not, and can- 

 not, be made to retain these substances in the same degree, as they have not the same 

 absorptive requirements. 



For instance it will be found that a loose sandy soil, and a heavy clay one, possess 

 the absorptive power in the smallest degree. 



One of the principal requirements of the fruit grower is to know the cause as well as 

 the means for making the nutritive substances of the soil available for doing their work. 



