Appendix 129 



Analysis of Garden Soil. About a liandful of soil will be 

 required by each pupil. 



5. Describe the appearance of the soil Is it fine or in lumi)s ? 

 Does it seem damp or dry ? Can you see the separate particles of 

 mineral matter ? How large are these ? Is there any evidence of 

 vegetable matter in the soil ? 



6. Put some of the soil in an evaporating basin and over this 

 place a dry filtering fimnel. Warm the basin gently. Is any 

 moisture given oflf? 



7. Dry some of the soil at a temperature not greater than that 

 of boiling water, e.g. by spreading it out on a biscuit tin lid, and 

 laying this on a radiator. How have the appearance and properties 

 of the soil been changed by drying ? 



8. Crumble some of the dried soil as finely as you can with 

 your fingers. Then sift it through a sheet of clean wire gauz& 

 What fraction of the soil is fine enough to go through the gauze ? 

 Describe the portion which will not pass through the gauze. Count 

 the number of wires per linear inch in the gauze. 



9. Mix some of the soil with water in a flask. Let it stand. 

 How long does it take before the water becomes quite clear again ? 



10. Mix some more soil with water. Let it settle for 30 

 seconds only. Pour off the muddy water into a tall glass cylinder. 

 Add more water to the remaining soil, and pour off a second portion 

 of muddy water, adding it to the first, and so on until all the fine 

 mud is removed from the soil. Allow this muddy water ample time 

 to settle. 



11. When the fine mud has settled pour off the bulk of the 

 water ; stir up the mud with the rest of the water ; transfer it to irn 

 evaporating basin, and evaporate to dryness. 



12. Does this dried mud consist of very tiny grains of sand or 

 of some material different from sand ? Can you find out with a 

 microscope ? 



13. If the mud consists of real clay and not of sand it should be 

 possible to burn it into brick. Moisten the dried mud again. Roll 

 it if you can into a round clay marble. Leave this to dry slowly for 

 a day. Then bake it either in a chemical laboratory furnace or in 

 an ordinary fire. 



14. Return to the soil used in Question 10, from which only the 

 fine mud has been washed away. Pour more water on to it^ shake it 



