264 
NATURE 
[JuLy 13, 1899 
comparisons are drawn between the structure of the moon’s 
surface and that of the earth, and evidence is adduced of the 
existence, at the present time, of a remnant of the original 
lunar atmosphere. —Examination of sea-water drawn from 
different depths: variation of iodine compounds therein, by M. 
Armand Gautier. Examination of water taken from the sur- 
face of the Mediterranean shows, as has been previously found 
to be the case with the Atlantic Ocean, the entire absence of 
iodides and iodates, the whole of the iodine present being con- 
tained partly in microscopic organisms and partly in combin- 
ation with a complex organic substance which contains nitrogen 
and phosphorus, and is capable of dialysis. The total amount 
of iodine present is nearly the same for all depths, but the 
form in which it exists varies considerably. Thus, at the 
bottom of the sea iodine exists in the form of iodides and 
iodates to the extent of 0°305 milligramme per litre, and the 
quantity decreases with decreasing depth until it disappears 
altogether at the surface. On the other hand, the iodine con- 
tained in living organisms is greatest in amount at the surface, 
and gradually diminishes as the depth increases. The iodine 
present in the form of soluble organic compounds is much more 
constant in amount, the maximum quantity being found at a 
depth of 880 metres. The water of the Mediterranean appears 
to be somewhat poorer in iodine than that of the Atlantic, the 
total quantities found being 2°25 and 2:40 milligrammes per 
litre respectively.—Observations of Swift's comet (1899 a) 
made with the Brunner equatorial at the Lyon Observatory, 
by M. J. Guillaume.—On the suppression of trial methods in 
the calculation of parabolic orbits, by M. L. Picart.—On the 
transformation of surfaces, by M. E, O. Lovett.—On the surfaces 
of Voss, by M. C, Guichard.—-The groups of the order 16 A, A being 
an odd prime, by M. Le Vavasseur.—On the development of a 
uniform branch of analytic functions in a series of polynomials, 
by M. Paul Painlevé.—On two integrable equations of the 
second order, by M. E. Goursat.—On a class of equations to 
partial derived functions, by M. Ivan Fredholm.—Considerations 
on the works of MM. S. Lie and A. Mayer, by M. N. Saltykow. 
—Wandering globular sparks, by M. Stéphane Leduc. When 
two fine metallic points are connected with the poles of an 
electrostatic machine, and placed in contact with the sensitive 
film of a photographic plate resting on a metal surface, an 
effluvium is produced around the positive point, and a luminous 
globule appears at the negative point. This globule increases 
in size, detaches itself from the negative, and slowly wanders 
towards the positive, point; on reaching the latter the lumin- 
osity ceases, and the machine is found to be discharged. The 
phenomenon suggests a comparison with globular lightning. — 
The frequency of nervous oscillations, by M. Auguste Char- 
pentier.—On the nature and cause of the phenomenon of 
coherers, by M. Thomas Tommasina. An account of further 
experiments on the formation of conducting chains of metallic 
particles in coherers.—On the position of the points of magnetic 
‘transformation of nickel steels, by M. L. Dumas. The influence 
of chemical composition on the magnetic properties of steels is 
described and discussed. —On the volumetric estimation of zinc, 
by M. Pouget. In the new process here described the solution 
of zinc is treated with hydrogen sulphide and the precipitated 
zinc sulphide decomposed with a known amount of iodine solu- 
tion, the excess of the latter being subsequently determined by 
titration with thiosulphate.—On the preparation and properties 
of the arsenides of strontium, barium, and lithium, by M. P. 
Lebeau. The arsenides of the metals in question were obtained 
by the reduction of the corresponding arsenates with carbon at 
the temperature of the electric furnace. They are reddish- 
brown substances presenting a crystalline fracture, and are 
rapidly decomposed by water with evolution of hydro- 
gen arsenide and formation of the hydroxide of the 
metal.—A study of methylic oxymethylene-cyanacetate and 
some of its homologues, by M. E. Grégoire de Bollemont. 
Methylic, ethylic, and amylic oxymethylene-cyanacetates have 
been prepared from the corresponding ethereal salts, which have 
been previously described. These compounds exhibit the char- 
acteristics of strong monobasic acids, and may be looked upon 
as substitution derivatives of formic acid.—The use of tetra- 
chlorohydroquinone for the characterisation and separation of 
fatty acids, by M. L. Bouveault. Tetrachlorohydroquinone 
reacts with one and two molecules of the chlorides of fatty acids 
to form stable, well-crystallised compounds which are easily 
purified, and thus eminently adapted for the identification, and 
NO. 1550, VOL. 60] 
in some cases for the separation, of the acids. The physical 
properties of some of these compounds are described.—On the 
' presence in the animal organism of a soluble ferment which 
reduces nitrates, by MM. E. Abelous and E. Gérard. Ex- 
periments are described which show that the various organs of 
the body contain, in different proportions, a soluble substance of 
the nature of a ferment which reduces nitrates to nitrites. A 
temperature of 20-40° is most favourable to the reaction, 
which ceases altogether at _72°.—On the reducing power of 
urine, by M. Henri Hélier. The author determines the reducing 
power of urine by titration with potassium permanganate 
solution in the presence of sulphuric acid, the result being ex- 
pressed with reference to urine of normal concentration, as 
measured by the amount of urea present. In many diseases, 
the reducing power is characteristically higher or lower than 
the normal.—Contribution to the study of the bark of Rhamnus 
purshiana (Cascara Sagrada), by M. Leprince. The presence 
is demonstrated of chrysarobin, chrysophanic acid, and emo- 
dine.—Direct transformation of acetamide into ethylamine by 
hydrogenation, by M Guerbet. The reduction is effected by 
means of metallic sodium in the presence of boiling amylic 
alcohol.—On the secretion of diastases, by M. Dienert.— 
Peculiarities of the eruption of Vesuvius, by M. Matteucci. 
CONTENTS. 
Saunders’s British Birds. By R.L. ....... 241 
As Regards Regeneration. ByJ.A.T. ..... 242 
Westra frican) Fetishie mmm Mises tel. ¢- tei meres 
Our Book Shelf :— 
‘Catalogue of the Library of the Royal Botanic 
Gardens, Kew” 366 (OME eg a al 
Davis (J. and W.): ‘The Larvz Collector's Guide and 
Calendar”. .SceeeenenCic: + +) +) oat eme A 
Letters to the Editor :— 
A Lecture Experiment on the Relative Thermal Con- 
ductivities of Various Metals. (J//ustvated.)— 
Edwin Edsertueacmeecne: = « «nema 
The Electrical Resistance of the Blood.—Dr. Dawson 
Stitdlgoes Gus og 4 6 6 Gio eOEEIDo 5 o.6 > 
School Laboratory Plans.—T. S. Dymond .. . . 245 
The Origin of the Doctrine of Compensation of Errors 
in the Infinitesimal Calculus.—Philip E. B. 
Jourdain! |). {ey tee men elie te. /> |cieal eanene 
Robert Browning and Meteorology. By B. W.S.. 245 
A Plague of Frogs. —F. H. Fortey. ..... .. 246 
he University of London. . - . + - inl mnuee4o 
The Life of a Star. (Wzth Diagrams.) By Prof. 
JafPerry, F..RiS se eeemeen Seni). =. (ieee meey 
William Henry Flower, K.C.B., F.R.C.S., LL.D., 
DiC... Sc. Di; WaReSeehe219., 0). 12-5. bysbrots 
Ev Ray ankestenslaReoumit-) -7- - -  -teaneutemnneesc 
The Duties of Provincial Professors .. . ... . 255 
Government Grant in Aid of Antarctic Exploration 256 
LS). Mii i O'S ob 14 eMoD Tg Yolo ol) BRO 
Our Astronomical Column :— 
Gomet:1899.ai(Swifk)emeeeecres Gli. = =: | eeeneinen eRZOO 
Tempel’s Comet ‘1899 ¢ (1873 II.). . . ..... + 260 
The New Allegheny Observatory ....... . . 260 
Leeds Astronomical Society ..... . . 260 
Theory of the Motion ofthe Moon. By P,H.C. . 260 
Investigations of Double Currents in the Bosphorus 
and Elsewhere .,..iureeiieec = + EOL 
University and Educational Intelligence ..... 263 
Scientific Serials .... Pie (ite |). TSR EzOS 
Societies and Academiesimuss:) -0-0- -°- |») me EzOS 
