Appendix — Sylktbiis of_ Laboratory Wo)'J{. 271 



\ 

 have a strip of white paper pasted vertically upon it to 

 receive the name of the stadent and other data. 



Each student weighs or measures the volume of 50 

 fresh seeds of the bean, pea or Indian corn in the manner 

 described above. Having noted the weight or volume 

 in his notebook, he pours the seeds, with the water, into 

 one of his bottles, corks the latter and writes his name, 

 with the date, on the paper pasted on its side. He then 

 repeats the process with seeds of the honey locust, yellow 

 wood or some other seed that does not readily absorb 

 cool water, and after recording the data in his notebook, 

 places the bottles in a warm place until the following 

 day, when he again determines the weight or volume of 

 the two kinds of seed. The seeds placed in the flrst bot- 

 tle will usually be found to have nearly or quite doubled 

 in size, while those -in the second bottle have scarcely 

 swollen at all. / 



Xext, show the class a sample of the second lot of 

 seeds that have fully swollen from soaking in hot water. 

 Impress upon their minds the fact that while most seeds 

 readily absorb moisture at ordinary temperatures, a few 

 kinds do not, and seeds of the latter class need to be 

 soaked cautiously, before planting, in hot water (27d). 



The rate at ichich seeds absorb water depends 



a — Upon the tcater content of the medium (27). AVeigh 

 3 samples of navy beans. Place one sample in water, a 

 second in very damp earth and the third in slightly 

 damp earth. Weigh again the next day and compute 

 the water absorbed by the three lots. ^ 



b — Upon the points of contact. AVeigh 2 samples of 

 navy beans, placing one sample in moist soil without 

 compacting, and the second in the same kind of soil well 

 compacted about the seeds. Determine the water ab- 

 sorbed by the two samples the next day. .< 



c — Upon temperature. Eepeat the above with 2 sam- 

 ples of navv beans, ijlacing one lot in a temperature of 

 80° to 90° F., and the other in 40° to 50° F. -" 



Other means of using the apparatus shown in Fig. 176 

 will occur to the thoughtful teacher. It may be used 

 for determining sj)ecitic gravities by dividing the weight 

 by the volume. 



