27 



bacteriology, and farm crops. Several courses of instruction are 

 ottered in each of these divisions, and in each case instruction is given 

 by the laboratory method, as well as hy text-ljooks, lectures, and 

 reference readings. Two laboratories are provided for the work in 

 soil fertility. One of these is used for the analysis of soils, fertilizers, 

 and manures; for the determination of the elements of plant food 

 contained in plants and plant products, and for the preparation of soils 

 for pot culture experiments, which include the use of sand cultures, 

 water cultures, and soil cultures, with the addition or elimination of 

 any or all of the ditferent elements of plant food (PI. Ill, tig-. 1). 

 The second is the pot-culture laboratory (PL III, fig. 2), which is 

 located in the greenhouse near the ag-ricultural building, and in which 

 the pot-culture experiments are carried on by the student as a part 

 of his regular laborator^^ practice. The soil fertility analytical labora- 

 tory is provided with desks for IS students' places, each desk Ijeing 

 made double, so that by working- two sections 36 students can be 

 accommodated. All apparatus necessary' for the analysis of soils, fer- 

 tilizers, etc., is provided, including analytical balances, digestion 

 furnaces, distillation apparatus, glass and porcelain ware, etc. The 

 laboratory is provided with a hood under which operations which 

 give off poisonous or disagreeable fumes or odors are performed. The 

 desks are piped for g-as, compressed air, vacuum and water, and pro- 

 vided with sinks and waste pipes. The fertility pot-culture labora- 

 tory is provided with suitable tables and with several hundred glazed 

 pots of different sizes suitable for pot-culture experiments. Most 

 of the water used in the pot-culture experiments is drawn from a 

 -JrOO-barrel cistern, which is kept full of exceedingly pure soft water 

 collected from the slate roof of the ag-ricultural iKiilding, which is a 

 quarter of a mile distant from the central heating- plant of the uni- 

 versity, and hence is very free from coal smoke, etc., from the chim- 

 neys. For special purposes, distilled water is provided and, when 

 necessary, nitrogen-free water is used. 



The soil physics laboratory (PI. IV, lig. 1) is provided with a suffi- 

 cient number. of desks to allow 24 students to work at one time, and, 

 by running two sections, 48 students can be accouunodated. This 

 lal)oratory is well equipped with the apparatus necessary for studying- 

 the physics of soil, including centrifugal machines and shaking appa- 

 ratus used in mechanical analyses (tig 1), microscopes, balances, 

 compacting apparatus, apparatus for determining the water content, 

 absorptive capacity, water-holding power, and specific gravity of soils; 

 several electrical instruments for the determination of temperature, 

 moisture, and soluble salt-content of soils; a 3-horsepower electric 

 motor with a line shaft, counter shaft, belting, etc. ; elutriators, fur- 

 naces, sieves, and much other general apparatus. The laboratory is 

 also provided with a side table, hood, large drying oven, and store- 



