230 SCIENTIFIC AGRICULTURE. 



while the compounds of the crenic and apocrenic acids remain 

 soluble, and may be separated by washing in water. (Johnston.) 

 To detect the presence of lime, take 100 grains of a soil and 

 mix well with half a pint of cold water, and then add half an 

 ounce of muriatic acid, stirring the mixture frequently : let it 

 stand a few hours to settle, then pour off the water and fill the 

 vessel with water to wash out the excess of acid ; when the 

 water is clear, pour it off, dry the soil and weigh it; the loss 

 from the first weight will show the quantity of lime sufficiently 

 near for all practical purposes. (Gaylord.) 



To determine the amount of sand, take a given quantity of 

 soil and boil it in water till it is thoroughly incorporated with 

 it, then pour the whole into a glass vessel and leave it till the 

 sand subsides: the clay remains in a state of mixture with the 

 water, which should be poured off and the sand dried and 

 weighed. If the sand contains lime, it may be separated by 

 muriatic acid as above directed. 



The amount of clay may be very nearly ascertained by 

 evaporating the water which was poured off of the said, 

 the residue will be mostly clay. 



To detect the presence of oxide of iron, mix a quantity of 

 soil with water, pour on muriatic acid and stir the mixture ; 

 let it stand a few hours and dip a piece of oak bark into the 

 solution, if the bark is colored brown or black, iron is present. 

 " To detect the presence of other salts, boil a portion of soil 

 in water, pour off the water and evaporate it, when the salts 

 may be obtained in crystals. 



If the salt is a nitrate, it has a cool pungent taste, and 

 ignites when thrown on coals of fire. 



If it be common salt, (muriate of soda,) it burns with a 

 crackling noise, and is also known by its taste. 



Sulphate of soda puffs up by heat, gives off a watery vapor 

 and leaves a dry white mass." 



These directions are sufficient to enable any one to make a 



