45i 



the soluble salt.s in soils; apparatus for the mechanical analysis of 

 soils: a steam dn'ing oven and a hot-air drying oven (tig. H); trays and 

 case, sampling auger, and sampling tul)o for tield work in soils; a 

 torsion balance and a numl)er of other l)alances; four compound micro- 

 scopes and one micrometer slide; a iuim])er of samples of tj^pical soils 

 from other States, as well as samples of Michigan soils, to which 

 samples additions arc being made as rapidly as opportunity permits; a 

 grade level and rod; specific gravity buUis, drying tubes, and sundry 

 glass and rul)ber tubing and glassware. The room has about 120 

 square feet of ]:>lackl)oard. 



The college farm comprises over 400 acres, not including the campus, 

 orchards, gardens, stock yards, and the experiment station plats. It 

 is divided into twent}' pasture, tield, and wood lots. At present the 

 several acreages are al)out as follows: Woods, 140; wild pasture, 30; 

 tame pasture, 37; hay, (>9; and roots, cereals, and forage crops, 141 

 acres. The soil is a drift soil and ranges from a sand}^ soil to a line 

 clay soil, all of which is interspersed with coarse gravel and hard heads 

 and bowlders. The farm machinery is up to date in eveVy particular 

 and includes a large collection of modern types of implements and 

 machines, as well as some of the older types, which are used by the 

 students in making comparisons of draft, work, effect on soils, etc. 



The library contains over 21,000 bound volumes and about 5,000 

 pamphlets, and is rich in scientific works. The tables of the reading 

 room are supplied with all the leading agricultural papers and journals. 

 In matters concerning crops and soils reference is made, first of all, 

 proba))ly, to station litei-ature, then to Storers Agriculture, King's 

 works, and others of Bailey's Rural Science Series, and the Kotham- 

 sted reports. 



Exhibit No. 5. 



A FEW OF THE PRACTICUMS IN AGRONOMY. 



The Jiioreiiit'iil of <iir tJimngh iHjf'ercnt. .loils. 



Description of apparalux. — The apparatus used for the study of air movements 

 through soils consists of an aspirator, as shown in tig. 4, and 12 brass tubes 16 

 inches in height and having a diameter of 3 inches. These soil tubes are all filled to 

 the depth of 1 inch with a coarse sand, and above the sand are filled to a depth of 12 

 inches with tlie different soils indicated in the table. By means of apparatus pre- 

 pared for the purpose the soils are introduced into the tubes and packed so that any 

 difference in the pore space in the soils must be due to the physical properties of the 

 soil. It will be seen that the variation of size of soil grain, variation in the propor- 

 tions of large and small grains, variation in amount of organic- matter present, etc., 

 must be the factors resulting in the differences in the rates at which the air moves 

 through the soil. 



Observe that we have not the conditions in the soil in the cylinders that we have 

 in the soil in the field, and that with this apparatus we are studying only the effects 

 resulting largely from the i)roperties named. 



