1824 
bottom of the cabinet , With four to five pounds of pressure, it requires 
but a 8 light turn of the valve, to give all the steam: needed. If too 
much steam is turned on, there will be considerable leakage and this 
is to be avoided, We make our drawero so that when .slightly heaped 
they hold, as indicated above, just about half a bushel of, soil. This 
is as much soil as one wants to lift about. Those who have had the 
experience of lifting two or three bushel bags of sloppy soil out of 
an autoclave know something of the back-breaking feature of this job. 
Furthermore, breaking the soil up in small quantities gives, the steam 
opportunity to penetrate it. This is further aided by the wire mesh 
bottom of the drawers. A piece of single thick burlap is placed in 
the bottom of each drawer. 
The drawers when put into the cabinet are staggered - that is, 
the first drawer at the bottom of the box or cabinet is pushed all the 
way in, the second is left about an inch from the, back of the box, and 
the next one is pushed in. This gives the steam a chance to follow 
up, over, and under each drawer. We find by experience that one hour's 
steaming as described will effectively destroy nematodes and mycelium 
and spores of the more common fungi infesting the soil. The tempera- 
ture of the treated soil for the last thirty minutes will average 80° 
to 85° C. Many tests have been made with the common . nematode , Meterodera 
radieicolq. Fragments of infested roots and the whole root growth of num- 
erous plants badly infested with the nematodes have been buried in the 
soil and subjected to the treatment as outlined. In all cases the nema- 
todes have been killed. Furthermore, no .nematodes, have, been found on 
the roots of plants grown in treated soil, although thousands of plants 
have been examined. Soil treated by this method does. not become soggy. 
It comes out of the cabinet in excellent physical condition, mealy,, and 
of good texture,. No, good gardener will object to it as a potting soil 
if it is in good condition when put into the apparatus. The eoil should 
not be steamed when oyerwet, 
.2. The Can Method of Soil Treatment. . (Pl> .318. ) There are many 
places and times when it is important to treat a small quantity of soil 
and when steam boilers are not available or in operation. .Ip.meet such 
a contingency we use a simple and inexpensive outfit consisting of a 
large galvanized can provided with a lid, a simple .steam generator con- 
sisting of a baking pan provided with a special lid, and a two-burner 
oil or gas stove. The apparatus assembled and taken apart is shown in 
the figure. The steam generating part of this apparatus, was, developed 
by the Dairy Division, Bureau of Animal Industry, U. S. : Department: of 
Agriculture, and is designed primarily for the sterilization of milk 
cans and milk receptacles. The soil to be heated is properly mixed 
and 8 if ted, and then put in half -bushel bags. A false bottom made of 
wooden slats is put in the galvanized can. The false bottom stands 
