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must be supplied by the cultivator; — and that the chief art 

 *' of agriculture depends upon the collection and preserva- 

 tion of those manures which contain ammonia in the 

 " greatest quantities." The loss in this kingdom of liquid 

 manure, which abounds in this substance, has been estimated 

 at an annual value of £7,000,000 sterling ! But since 

 the publication of " Chemistry applied to Agriculture and 

 " Physiology," farmers are slowly opening their eyes to its 

 value, and a better collection and preservation of it is now 

 being made. 



But if I mistake not. Professor Liebig points out in his 

 work just published, " Organic Chemistry applied to Phy- 

 " siology and Pathology," a discovery of no less value to 

 agriculturists than any of those in " the Agricultural Che- 

 " mistry." It is respecting the necessity of warmth to animals 

 during the time of their fattening ; and also of a due supply 

 being given them of nitrogenised food. In that splendid 

 treatise, which will be as enduring as the science of medi- 

 cine, he indicates that in man and animals the body is a 

 furnace to be supplied with fuel, — that the carbon of the food 

 is the fuel which is burnt or oxydised by the oxygen of the " 

 atmosphere taken into the lungs; and the mutual action 

 between the elements of the food and the oxygen conveyed 

 by the globules of the blood to every part of the body, is the 

 source of animal heat ; — and that the amount of nourishment 

 required by the animal body, must be in direct ratio to the 

 quantity of oxygen taken into the system : — that the number 

 of respirations, or the quantity of oxygen absorbed, is smaller 

 in a state of rest than during exercise : — that the quantity of 

 food must depend upon exercise, and that an excess of food 

 is incompatible with deficient exercise. In order to keep up 

 in the furnace a constant temperature, we must vary the 

 supply of fuel according to the external temperature, e.^ 

 according to the supply of oxygen. Our clothing is an 



