456 



CENTRAL SCIENTIFIC CO., CHICAGO, U. S. A. 



No. 12404. 



No. 12420. 



No. F2333. 



12404. SOIL ACIDITY TESTER, Truog. This apparatus is made after specifications by E. Truog of 



the University of Wisconsin. The principle employed is an entirely new one and indicates 

 clearly not only the presence of soil acidity but the degree of the acidity. Consists of a 

 specially designed Alcohol Heater together with a Graduated Boiling Flask, Brass Measuring 

 Cup, Brass Measuring Spoon, Spatula, and all necessary reagents. The test is completed in 

 from 10 to 15 minutes, and the presence of acidity is shown by discoloration of the white 

 test paper used, and the degree of acidity by the exact color assumed by the paper as com- 

 pared with a chart of standard colors furnished. A full set of directions giving exact de- 

 scription of the test with all precautions is included. Complete as described, in a neat hard- 

 wood carrying case $7.50 



Parts for No. 12404. 



12405. FLASK, 300 cc capacity, with mark at 100 cc 75 



12406. MEASURING CUP for soil 20 



12407. MEASURING SPOON for reagents 15 



12408. TEST PAPER, 50 sheets in glass vial per vial .15 



12409. SET OF REAGENTS, sufficient for making 50 tests, consisting of a bottle containing 55 grams 



of a mixture of calcium chloride anfl zinc sulphide specially prepared, vial of test paper (50 

 strips), and measuring spoon 75 



F2333. SPECIFIC HEAT APPARATUS (modified design after Prof. A. G. McCall) for determining 

 the Specific Heat of Soils; may also be used for determining the specific heat of any substance. 

 Consists of a double-walled heater or steam jacket with large rectangular base and support 

 rod, and a double-walled calorimeter. Both heater and calorimeter are of very substantial 

 construction, and are well insulated. The heating chamber extends through the heater and 

 is closed at both ends with heavy insulated covering. The top cover has two openings, one 

 for a thermometer, and the other for suspending the sample to be tested. The clamp which 

 holds the heater rests on a collar which is clamped to the support rod, so that when the sam- 

 ple has come to a constant temperature the lower cover of the heater can be swung back out 

 of the way and the heater rapidly swung around to a position over the calorimeter. The 

 transfer of the specimen from heater to calorimeter can thus be readily and quickly effected. 

 Heater and calorimeter complete as described, but without thermometers 30.00 



F2334. CALORIMETER only of No. F2333 without thermometers 10.00 



12420. TANK for holding water, of galvanized iron, 12 inches in diameter, with drop handles, for use 

 with all soil tubes 14 inches long, or under (e. g., No. 12492) 1.90 



12422. TANK for holding water, of galvanized iron, 12 inches in diameter. For use with soil tubes 3fi 

 inches long, or under; made especially for No. 12444 Tube 3.50 



12424. TANK for holding water, of galvanized iron, 26x6x6 inches. For use in all capillarity experi- 

 ments. Used with Tubes Nos. 12444-12464 1.80 



