NALOTEE, 
[JANUARY 14, 1904 
daris (?); and eighteen genera are recorded from the 
Cainozoic series. Most of these last-named genera are still 
living, and some of the species have a wide geographical 
distribution and a considerable range in Tertiary time. 
Mr. A. Lucas has prepared, for the Public Works 
Ministry at Cairo (1903), a report on the soil and water of 
the Wadi Tumilat lands. It appears that this alluvial tract 
formed part of ‘‘ the land of Goschen,’’ and was a fertile 
tract until ruined by the Ismailia Canal. The author points 
out that this high-level canal passes through a porous soil, 
and the seepage-water has not only raised the general level 
of the subsoil water, but has brought to the surface in many 
places salts of soda which have proved more or less in- 
jurious, the sodium carbonate being most harmful to 
vegetation. Wind also helps to distribute the efflorescent 
salts. The remedy consists in a thorough system of drain- 
age, and in frequent washing of the land. 
WE have received a copy of the *‘ New and Revised Edition 
of a Geological Map of the Southern Transvaal,’’ by Dr. 
F. H. Hatch (Stanford, price 20s. in sheet, 25s. in case), 
with explanatory pamphlet (1903). The scale of the map 
is a little more than four miles to an inch, and it includes 
an area bounded on the north by Pretoria, on the west by 
Ventersdorp and Klerksdorp, on the south by the Vaal 
River, and on the east by Greylingstadt and Heidelberg. 
It is very clearly printed in colours, and the farm boundaries 
are shown. Although admittedly a sketch-map, it will be 
of great service in representing the present state of know- 
ledge with regard to the extent of the coal-bearing strata, 
the auriferous rocks and other mineral resources, not to 
mention the Dolomite series, which is economically of great 
importance as the source of perennial streams and as 
furnishing the present water-supply of Johannesburg. 
Systematic and distributional arrangements of the genus 
Polygonum in India have been prepared by Captain Gage, 
and are published in the Records of the Botanical Survey 
of India. The horizontal distribution of the species through- 
out certain sub-subareas of India compared with their distri- 
bution in other countries is well shown in one set of tables, 
and another set indicates the vertical distribution. From 
the latter it will be observed that Polygonum viviparum 
shows the greatest vertical range, namely, from 4000 to 
17,000 feet ; Polygonum tortuosum and Polygonum sibiricum 
reach to the same upper limit, but are not found below 
11,000 feet. 
In the notice of ‘* Le Point critique des Corps purs’’ in 
last week’s NATURE (p. 217) it should have been stated that 
the author of the book is Prof. E. Mathias. 
Messrs. Watts aNd Co. have issued for the Rationalist 
Press Association sixpenny editions of ‘‘ Science and Specu- 
lation,’ by Mr. C. H. Lewes, and of Mr. Edward Clodd’s 
“Story of Creation.’’ The latter volume contains eighty- 
six illustrations and tables. 
Tue Brin Oxygen Companies, the London address of 
which is now Elverton Street, Westminster, S.W., have 
issued a convenient little diary which is provided with much 
useful information. Not only are full particulars of the 
prices of the apparatus made by the companies and of the 
compressed gases supplied by them included, but also a 
series of hints to users of compressed gases in the form of 
medical notes, notes for lanternists, for blowpipe users, and 
on extreme refrigeration. In addition, the booklet contains 
a cylinder record and instructions for using liquefied carbon 
dioxide. 
NO. 1785, VOL. 69} 
WE have just received an advance copy of Merck’s English 
catalogue of fine chemicals. The list of chemicals is very 
comprehensive, and is probably the most complete published 
in this country. We note that Merck’s present factory in 
Darmstadt will soon be replaced by entirely new works, now 
in course of erection. 
In the current number of the American Journal of Science 
Mr. J. C. Blake points out that soluble silver compounds. 
are formed in the preparation of colloidal silver solutions by 
| sparking between silver electrodes under water. It seems 
probable to the author that these compounds may play an 
important part in the peculiar actions exhibited by colloidal 
metal solutions, which, from the similarity of their behaviour 
to that of ferments, have been styled by Bredig inorganic 
ferments. 
In the Proceedings of the American Academy of Arts and 
Sciences Mr. G. P. Baxter describes some further experi- 
ments relative to the atomic weight of iron, an entirely new 
method—the analysis of ferrous bromide—being employed. 
These new experiments confirm the result, 55-88, previously 
obtained by Richards and Baxter for the atomic weight by 
the reduction of the oxide, and indicate that the value, 56-0, 
usually employed is appreciably inaccurate. 
A new form of electrical resistance furnace was described: 
by Dr. Frélich at the last meeting of the German 
“Bunsen ’’ Society for Applied Physical Chemistry. In- 
stead of employing carbon cores as the immediate source of 
heat, the sides of the furnace itself are utilised, the furnace 
being constructed of some specially suitable material the 
nature of which has not been divulged. The mean tempera- 
tures reached in a core furnace and in that described by the 
author under comparative conditions were found to be 12007 
and 1600° C. 
Tue first number of a new review, 
chemisches Centralblatt, has just been issued. It is not 
intended as a medium for the publication of original worl, 
but as a comprehensive centralising review of progress ini 
physical chemistry, the extraordinarily rapid rise and de- 
velopment of which during the last decade is almost unique 
in the history of science. The abstracts are to appear either 
in German, English, or French, and, so far as possible, will 
be furnished by the authors themselves. The review will be 
issued twice a month, and will no doubt be a valuable aid 
to the numerous chemists who desire to keep abreast of 
physicochemical literature. 
The rate of oxidation increases as the pressure diminishes, 
and no completely satisfactory explanation of this apparent 
observations on the subject. It appears that the presence 
of a small quantity of water is necessary for the oxidation, 
and that the quantity left after drying with sulphuric acid 
is that which allows reaction to proceed most rapidly. The 
results of experiments carried out at higher pressures con- 
tradict the usual statement that phosphorus only reacts with 
oxygen at low pressures, and the author finds that the re- 
action in these circumstances is in agreement with the 
mass action law. 
A NOVEL reducing agent is described by Dr. Stoermer in 
a recent number of the Berichte. He has found that in a 
considerable number of cases compounds containing the 
| group —CH,.CO— are reduced by heating with phosphorus 
Tue oxidation of phosphorus is a reaction which, in spite — 
of its apparently simple nature, exhibits many anomalies. — 
exception to the law of mass action has yet been given. 
In the current number of the Journal of the Chemical — 
Society Mr. E. J. Russell contributes a further series of 
re 
ea i 
the Physikalisch- — 
