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



451 



No. 12324. 



No. 12336. 



12314. 

 12316. 



12318 

 12324 



ORGANIC MATTER JAR. A 1-gallon glass jar provided with a round hole for drainage, 1 cm 

 in diameter, located 1 cm above the bottom $0.75 



PAN, of metal, water tight, 4^4x4*4x1% inches. For use in Drying Ovens 25 



PAN, of zinc, 6^x6^x1% in., as used in No. 12222 Absorption Apparatus. These pans are 

 water tight and will be found convenient for use in drying ovens 30 



PAN or BOX, of zinc, 4x4x4 inches, for volume-weight experiments 50 



SAMPLE CANS OR BOXES, see general heading Boxes. 



PENETROMETER, for determining the firmness of soil due to its cohesion, by means of the 

 resistance offered to the introduction of a sharp instrument. The apparatus is essentially as 

 described in the Bulletin referred to, but is supplied with a device for making electrical con- 

 tact when the soil has been penetrated to the desired depth, as suggested by Prof. Charles F. 

 Shaw of the University of California. Complete as illustrated. (See Bulletin No. 50, Bureau 



of Soils) 50.00 



12328. PERCOLATION APPARATUS, McCall's, for determining percolation of water through soils. 

 Glass percolator, 1% pint, with brass extension having lateral tubes. Complete with rubber 

 gasket, copper gauze, etc 6.50 



PERCOLATORS, see general heading Percolators. 



PESTLE, Rubber, for preparing soils for analysis; 7 inches long, wood handle with rubber 

 tip 30 



PLASTICITY APPARATUS, for determining the effects of lime on plastic soils. Consists of a 

 clamp with two knife edges about 4 inches apart, across which the briquet to be tested is 

 placed for breaking, a heavy canvas bag for holding weights and shot and one No. 12337 

 Mold, 5 inches long, 1 inch wide and % inch deep, as illustrated. For those who wish a mold 

 of more accurate dimensions, the purchase of No. 12338 Mold is recommended. (This design 

 has been developed from the original in use at the University of Illinois, in co-operation with 

 the Soil Physics staff of the University) 2.50 



MOLD only o'f No. 12336 ., 25 



MOLD, improved form, for No. 12336, as suggested by A. F. Gustafson of the University of 

 Illinois. Of cast brass, accurately milled to shape. All molds are therefore identical and 

 always occupy the same position on the table, so that the bricks of soil obtained are accurate 

 and uniform in shape. Inside cross section % square inch, length, 5 inches 1.00 



12332 

 12336 



12337. 

 12338. 



