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i6 cu. ft. of earth which was easily heated in one hour's time when 

 three lengths of 2 -in. tile were used and a pressure of 4 or 5 lbs. of 

 steam. With the small lead pipe it was found that it was impossible 

 to heat the soil after running it for a number of hours. The method 

 just described is especially adapted to sterilizing soil in the bed 

 where it is subsequently to be used in growing some greenhouse 

 crop subject to nematodes. It should be stated, however, that cer- 

 tain beds are more suitable for this purpose than others. Soil can 

 be more effectually heated in a narrow bed than in a wide one. 

 Many of our cucumber growers raise their plants in a bed 15 or 18 

 in. wide, 8 to 12 in. deep, and 50 to 100 ft. or more in length. Beds 

 approximating these dimentions could be easily heated in a short 

 time at little expense, and in a cucumber house it would be most 

 desirable to construct them after this manner. Not unfrequently, 

 however, cucumber houses are not provided with benches but the 

 vines are grown directly in the ground soil. In this case should 

 sterilizing become necessary, the earth in which the plants are grow- 

 ing can be separated from the remaining soil by means of 12 in. 

 boards or plank and this lot of earth caji be'tiled and then treated. 

 The boards or plank arranged in this manner restrict the amount of 

 soil to be treated and prevent contamination from the untreated. In 

 case pots are used as frequently happens in tomato culture the earth 

 can be sterilized in a special bed or the pots containing the earth 

 can be placed in a tight box and sterilized, although this latter 

 method is not so practical as pots take up more room than soil 

 placed in a bed. For sterilizing small quantities of earth we make 

 use of an ordinary small house boiler which heats our laborator}^ 

 and seldom indicates more than 3 or 4 lbs. pressure of steam. This 

 is connected with a box, (see fig. II., i, 2, and 3), containing 15 cu. ft. 

 of earth, in the bottom of which is buried three lengths of tile sup- 

 plied with steam from the boiler. With a pressure of 3 or 4 lbs. of 

 steam the box can be easily heated to 212° F. in one hour's time and 

 this amount of earth will fill about fifty 10 in. pots. A small bed of 

 this description would be exceedingly convenient for florists in steril- 

 izing earth for such pot plants as cyclamens etc. Another conven- 

 ient arrangement for sterilizing which we use for a variety of pur- 

 poses is shown in fig. II., 4, which represents a cross section of a box, 

 but it is not adapted for sterilizing earth except when in trays or 

 pots. This is simply an ordinary zinc lined box. It is provided 



