1904] CURRENT LITERATURE 475 
the activity of the cambium is given some attention, but no general conclusion is 
established.—RAymonpD H. Ponp 
SEVERAL METHODS in cytological technique are described by OsteRHOUT.35 
One of these is a substitute for the universally used paraffin method. Though 
various soaps have been tried and found unsatisfactory, OsreRHOUT has developed 
a method with cocoanut oil soap which he regards as superior to the paraffin 
method. It is better to make one’s own soap, using 70°¢ of cocoanut oil to 38.5°° 
of 28 per cent. solution of caustic soda in water. The tissue is placed in warm 
water and the soap added gradually until a fairly strong solution is obtained. It 
may then stand in the bath for two or three days. When sufficiently firm, the 
block may be cut. The sections form a perfect ribbon and do not crumble or 
crush as is so often the case with paraffin. They may be fixed to the slide with 
albumen. In trying this method one should have the full paper at hand.— 
CHARLES J. CHAMBERLAIN. 
THE GREAT and, indeed, almost violent interest taken in some quarters in 
Bulletin 22 of the U. S. Bureau of Soils, will cause the appearance of Bulletin 
23 to arouse some curiosity at least.3° The subject-matter of the present bulle- 
tin falls into two separate portions. The first presents a series of rather incom- 
plete experiments on the movement of soil water, together with some data on the 
rate of imbibition of seeds in contact with moist soil, while the second portion 
deals with experiments on the growth of plants in culture media. ‘The first mass 
of material is not important, but the second presents a discovery which, if sub- 
stantiated and generally true, is as far-reaching and important as it is unexpected. 
This discovery is, briefly, that the good or bad characteristics of a soil are trans- 
mitted to its aqueous extract. This is shown by growing wheat plants in pots 
of the soils to be compared and in bottles of watery extract of these same soils. 
In such an experiment the different water cultures show the same relations as do 
the pot cultures. The plants were compared in respect to size and general appear- 
ance and to amount of transpiration. That this difference in soils and their 
solutions is not one of mineral salts is shown by the fact that good and poor Cecil 
clay show the difference markedly, although practically identical in chemical 
nature. It is suggested that the bad properties of at least some sterile soils pred 
be due to organic substances. The bulletin is essentially a report of progress an 
all of its lines of investigation will need further work before they can be regarded 
as established.—B. E. LIvINGSTON. 
35 OSTERHOUT, W. J. V., Contributions to cytological technique. (1) weer 
freezing microtome. (2) Fixation im vacuo. (3) A simple slide holder. iw as 
method of mounting in aqueous media. (5) Embedding microscopic i. mh 
Embedding with incomplete dehydration. Univ. of California Publications. otany 
2:73-90. 1904. 
36 Wuttney, M. and CAMERON, F. K., Investi 
gations in soil fertility. U.S. Dept. 
Agric., Bureau of Soils, Bull. 23. 1904. 
