10 THE FLORIST. 



the soil — its importance is at once apparent. And yet, how completely 

 ignorant of the subject were mankind in general until lately ! 



That concentrated force of scientific discoveries and mechanical 

 inventions which so wonderfully increased the productive powers of so 

 many mechanical arts and manufactures at the close of the last and 

 the commencement of the present century, also set in action the wheels 

 of horticulture and agriculture, thereby augmenting the productive 

 powers of the soil in a ratio proportionate to the degree of scientific 

 knowledge brought to bear on the subject. To the practical application 

 of chemistry and geology are we principally to ascribe the rapid 

 progress made of late years in every department of gardening and 

 liarming. Geology informs us that the surface of our globe consists 

 everywhere of a more or less solid mass of rock, covered with a layer, 

 generally thin, of loose material ; that the upper part of these loose 

 materials forms the soil. 



The geologist has examined those rocks which lie beneath the soil, 

 and has discovered them to be very different in appearance and com- 

 position — some are sandstones, others limestones, and so on. These 

 rocks, when exposed to the action of the weather, are seen gradually to 

 crumble away ; in this manner are soils naturally formed, and they 

 consequently assume the character of those rocks. This at once 

 accounts for the diversity of soils. Armed with a practical knowledge 

 of this science, we shall be able to ascertain the nature of the soils we 

 cultivate, and shape our practice accordingly. But though geology tells 

 us the general character of land in a district — throws much light on the 

 nature and origin of soils, and on the causes of their diversity — still it 

 is chemistry which tells us that soils, of whatever kind, are made up 

 of two parts — an organic and inorganic part. It is chemistry that tells 

 us that vegetables are made up of two parts — an organic ani inorganic 

 part. It is chemistry which tells us that though vegetables not only 

 may, but actually do, derive a considerable portion of their organic part 

 from the atmosphere, they derive the whole of their inorganic part from 

 the soil. Chemistry also tells us that those soils which contain these 

 inorganic parts in greatest abundance are naturally the most fertile. 



It is not necessary that we all become professed chemists to be able 

 to ascertain the quantities of the different inorganic constituents in a 

 soil sufficiently accurate at least for all practical purposes. " The 

 instruments," says Sir H. Davy, "required for the analysis of soils are 

 few and but little expensive. They are a balance capable of containing 

 a quarter of a pound of common soil, and capable of turning when 

 loaded with a grain ; a wire sieve sufficiently coarse to admit a mustard 

 seed through its apertures ; an Argand lamp and stand ; some glass 

 bottles ; Hessian crucibles ; porcelain or Queen's ware evaporating 

 basins ; a Wedgewood pestle and mortar ; some filters made of half a 

 sheet of blotting paper ; a bone knife ; and an apparatus for collecting 

 and measuring aeriform fluids." " The chemical substances or 

 reagents required for separating the constituent parts of the soil are 

 muriatic acid, sulphuric acid, pure volatile alkali dissolved in water ; 

 solution of prussiate of potash and iron ; succinate of ammonia ; soap 

 lye, or solution of potassia ; solution of carbonate of ammonia, of muriate 

 of ammonia, of neutral carbonate of potash, and nitrate of ammonia." 



