LABORATORY PRACTICE 237 



6. Place in the metal frame (EC) a piece of cheese- 

 cloth sufficiently large to cover the bottom of the frame 

 and the sides. 



7. Into the frame introduce the mass of wet soil, packing 

 the soil down thoroughly and filling a little more than 

 flush full. 



8. With a sharp straight edge or knife, cut away the 

 excess, leaving the frame just flush full. 



9. Remove the wedge (G) and carefully remove section 

 (C) of the metal frame, and then carefully remove the mass 

 of soil. 



10. Place the mass of soil where it will remain at air 

 temperature for two days, then place in drying oven at 

 100 C., and allow to remain until completely dry. 



11. At the end of each 24 hours, measure the dimensions 

 of the mass of soil and make a record of time and measure- 

 ments. 



12. Determine the percentage of shrinkage up to the 

 time of each measurement. 



13. Repeat the experiment with the other kinds of 

 soil and compare the results. 



EXPERIMENT 12 

 Puddling Soils 



1. Procure an amount of mellow heavy field clay. 



2. Carefully dry so that the crummy structure shall 

 not be destroyed, and so that the clay shall not dry in 

 masses. 



3. Weigh 25 grams of the dry clay into each of two 

 funnels, having first carefully placed a properly folded 

 filter paper in each funnel and moistened. 



