242 CATECHISM OF 



Why have not rural employments been held in the highest 

 honor ? 100. What employment is most conducive to rationa. 

 enjoyment and long life ? 100. How did the Creator intend that 

 the farmer should thrive ? 100. How has He therefore made his 

 employment? 100. 



Chemically considered, what is the difference between good 

 soils and poor ? 101. Does a soil which the Creator has perfected 

 by those protracted agencies before spoken of, contain the 

 elements in Table I. ? 102. Is it almost wholly made up of them 1 



102. Do they exist in it in their elementary state ? 102. 



Do the binary compounds mentioned in Table I., either exist 

 in soils, or in some way contribute to their fertility? Table I.#nd 



103, 104, &c. What is sulphuric acid ? Tables I. How much of 

 this might be expected to be found in a good soil ? 103. In 

 what state? 103. 



What is phosphoric acid ? Table I. aad 47. How much of this 

 might we expect to find in a good soil? 103. In what state? 



What do you say of carbonic acid in soils ? 104. Of silicic acid ? 

 105. Of nitric acid? 106. Of water? 107. How does the food 

 of plants enter them ? 107. How much oxygen will water ab- 

 sorb or dissolve in itself? 107. How mflch nitrogen? 107. 

 How much hydrogen ? 107. How much carbonic acid ? 107. 

 How much ammonia ? 107. What does water do with these 

 gases? 107. 



What other substances does water dissolve and carry into 

 plants ? 107. How does the excess of water then leave the 

 plant? 107. What benefit in irrigating with pure water? 107. 

 What extra benefit in irrigating with impure water? 107. How 

 may such irrigation be considered? 107. 



What is said of the oxides of iron in soils ? 108. Of the oxides 

 of manganese? 109. Of potash? 110. Of soda? 111. Of lime? 

 112. Of magnesia? 113. Of alumina? 114. Of chloride of so- 

 dium ? 115. Of sulphuret of iron ? 116. Of sulphuret of hydro- 

 gen? 117. Of light carburetted hydrogen? 118. Of ammonia? 



Do these binary compounds exist as such in soils ? 121. If 

 not, how then ? 121. 



What do you understand by the inorganic part of a soil ? 122. 

 What by the organic part ? 122. A stick of oak wood contains 

 about 98 parts of organic matter to two of inorganic ; if you burn 

 it, where does the organic part go ? Into the air. What becomes 

 of the inorganic part ? It falls down as ash. What four elements 

 constitute organic matter? 122. Why are carbon, hydrogen, 

 oxygen and nitrogen, called organic elements ? 33. 



As vegetable matter decays, does it form organic acids ? 122. 

 How many ? 122. What are the names ? 122. What other or- 

 ganic acids are mentioned ? 123. What is the composition of 

 acetic acid (vinegar)? 123. What of oxalic acid (C^O^) ? 123. 



If oxalic acid should combine with potash, soda, hme, or some 



