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SCIENTIFIC SERIALS 
THE January number (N.S., No. 37) of the Quarterly Journal 
of Microscopical Science opens with an article entitled “Notes on 
Sponges,” by Prof. E. Perceval Wright. In this the author indi- 
cates some peculiarities of the structure of the sponge-body of 
Hyalonema mirabilis, and describes two new species of deep- 
sea sponges, namely 4 phrocallistes Bocaget, which is exquisitely 
figured by Mr. Ford, and the type of a new genus which the 
author names Wyvillethomsonia Wallichi. We cannot help 
protesting against this new generic name, as being barbarous in 
the highest degree. Mr. William Archer, of Dublin, continues 
his valuable descriptions of new or imperfectly-known fresh- 
water Rhizdpoda, and Mr. W. S. Kent describes and figures a 
curious new form of Polyzoon, from the Victoria Docks, where the 
animal lives attached to the surface of specimens of the Cordylo- 
phora lacustris. For this Polyzoén, which the author regards as 
the type of a new family (Homodietide) of the Ctenostomata, he 
proposes the name of Victorella pavida. A singular crustacean 
parasite found on WVerers cultrifera is described and figured by 
Dr. W. C. McIntosh. Besides these, we have a paper on the 
distribution of nerves to the vessels of the connective tissue in 
the hilus of the pig’s kidney, and on the ganglia connected with 
these nerves, by Dr. James Tyson, of Philadelphia ; an abstract 
of a dissertation on the minute structure of the human umbilical 
cord, by Dr. Koster; a translation of Dr. E. Van Beneden’s de- 
scription of his Gregarina gigantea (with a plate) ; and an abstract 
of an important memoir, by Dr. Kowalewsky, on the relationship 
of Ascidians and Vertebrates. The only original article on the 
microscope itself is one by Dr. G. W. Royston-Pigott, on 
certain imperfections and tests of object-glasses. This number 
also contains a review of Mr. Hincks’s ‘‘ History of British 
Hydroid Zoophytes.” 
IN the Geological Magazine for the present month (No. 67), the 
most important paper is the first part of a memoir on the sequence 
of the Glacial Beds, by Mr. Searles V. Wood, jun., in which 
the author indicates his views as to the best classification to be 
adopted in the treatment of these difficult deposits, and discusses 
the characters of the beds and evidence attamable as to the 
sequence of the phenomena attending their deposition. Mr. 
David Forbes publishes some remarks on the contraction of 
igneous rocks in cooling, in which he again maintains, chiefly 
from his own experiments, that the amount of this contraction is 
much less than is generally believed, on the authority of Bischof. 
His paper is really a vindication of himself from some remarks 
in a memoir by the Rev. O. Fisher. Mr. John Rofe describes 
some peculiar perforations observed in the lower surfaces of slabs 
of mountain Jimestone, at considerable elevations, in various 
localities, which have already been noticed by several writers, 
and ascribed by some to lithodomous marine mollusca. Mr. Rofe 
regards them as produced by snails, either by the rasping action 
of their odontophores alone, or by this aided by an acid salivary 
fluid. Mr. Ruskin continues his notices of banded and brecciated 
concretions. Mr. J. Clifton Ward remarks upon the denudation 
of the lake-district, which he ascribes chiefly to subaérial action. 
In a paper on the formation of the Chesil Bank, Mr. T. 
Codrington maintains, in opposition to Messrs. Bristow and 
Whitaker, that the streams coming from the land have had 
nothing to do with the production of this bank, or the excavation 
of the channel by which it is separated from the mainland. He 
ascribes the formation of this and similar banks solely ‘‘to the 
heaping-up action of waves breaking when they reach a depth of 
water about equal to their own height.” 
THE Revue des Cours Scientifiques for the 8th inst. contains a lec- 
ture, by Prof. Lorain, on the application of the graphic method to 
the clinical study of disease. Translations are likewise given of 
Prof. Helmholtz’s address to the meeting of German Naturalists 
and Physicians at Innspruck, and of Mr. Geikie’s account of the 
same meeting, published in the first number of NATURE. 
SOCIETIES AND ACADEMIES 
Lonpon 
Royal Society, December 16, 1869.—The following were 
among the papers read:—‘‘On the Thermodynamic Theory of 
Waves of Finite Longitudinal Disturbance,” by Prof. Rankine, 
F.R.S.; ‘‘On Approach caused by Vibration,” by Prof. 
Guthrie. The author observes that when a vibrating tuning- 
fork is held near to a piece of cardboard, the latter has a tendency 
to approach the fork. Starting from this experiment, a series of 
NATURE 
[ Fan. 13,1870 
experiments is described, having for their object the determina- 
tion of the cause and conditions of the fundamental observed 
fact. It isshown that no sensible permanent air-currents, having 
their source at the fork’s surface, are established ; and hence that 
the approach of the card to the fork is not due to the expansion 
of such currents, as in M. Clement’s experiment. The modifica- 
tions are examined which Mr. Faraday’s surface-whirlwinds ona 
vibrating tuning-fork undergo when the fork vibrates in the 
neighbourhood of a sensibly rigid plane. It is shown that a 
delicately-suspended card approaches the fork when either of the 
three essential faces of the fork is presented to the card, and that 
the approach takes place from distances far exceeding the range 
of Mr. Faraday’s air-current. That the action between the card 
and fork is mutual, is shown by suspending the latter. Also one 
vibrating fork tends to approach another in whatever sense their 
planes of vibration may be towards one another. The mean 
tension of the air surrounding a vibrating fork is examined by 
enclosing one limb of the fork ina glass tube. It appears that 
the vibrating fork displaces air. The question whether the equi- 
librium between two equal and opposite forces acting on a body is 
disturbed by submitting one of the forces to successive rapid, equal, 
and opposite alterations in quantity, is answered in the negative by 
an experiment which shows that the equilibrium of a Cartesian 
diver is not disturbed by submitting the water in which it floats 
to vibration. Various modifications are introduced into the 
nature of the surface which receives the vibrations, such as 
making it a narrow cylinder with one end closed, making it of 
cotton-wool, &c. It is found that in all cases the suspended 
body approaches the vibrating one. The author concludes that 
the effect of apparent attraction is due to atmospheric pressure, 
and that this pressure is due to undulatory dispersion. It is 
suggested that the dispersion of the vibrations which consti- 
tute radiant heat may cause bodies to approach, being pushed, 
not dulled.—‘‘On Abstract Geometry,” by Prof. Cayley. ‘‘I 
submitsto the society the present exposition of some of the 
elementary principles of an abstract 7-dimensional geometry. 
The science presents itself in two ways: as a legitimate extension 
of the ordinary two-and three-dimensional geometries; and as a 
need in these geometries and in analysis generally. In fact, 
whenever we are concerned with quantities connected together 
in any manner, and which are, or are considered as, variable or 
determinable, then the nature of the relation between the 
quantities is frequently rendered more intelligible by regarding 
them (if only two or three in number) as the co-ordinates of a 
point in a plane or in space; for more than three quantities there 
is, from the greater complexity of the case, the greater need of 
sucha representation; but this can only be obtained by means 
of the notion of a space of the proper dimensionality ; and to use 
such representation, we require the geometry of such space. An 
important instance in plane geometry has actually presented itself 
in the question of the determination of the curves which satisfy 
given conditions; the conditions imply relations between the 
co-efficients in the equation of the curve; and for the better 
understanding of these relations it was expedient to con- 
sider the coefficients as the co-ordinates of a point in a space 
of the proper dimensionality. A fundamental notion in the 
general theory presents itself, slightly in plane geometry, but 
already very prominently in solid geometry ; viz., we have here 
the difficulty as to the form of the equations of a curve in space, 
or (to speak more accurately) as to the expression by means of 
equations of the twofold relation between the co-ordinates of a 
point of such curve. The notion in question is that of a £-fold 
relation, —as distinguished from any system of equations (or one- 
fold relations) serving for the expression of it,—and giving rise 
to the problem how to express such relation by means of a system 
of equations (or onefold relations). Applying to the case of 
solid geometry my conclusion in the general theory, it may be 
mentioned that I regard the twofold relation of a curve in space 
as being completely and precisely expressed by means of a system 
of equations (P=0, Q=o, . . T=o), when no one of the func- 
tions, P Q, .. . T as a linear function, with constant or variable 
integral coefficients, of the others of them; and when every sur- 
face whatever which passes through the curve has its equation 
expressible in the form U=AP+BQ. . .+KT, with constant or 
variable integral coefficients, A+B...K. It is hardly neces- 
sary to remark that all the functions and coefficients are taken to 
be rational functions of the co-ordinates, and that the word in- 
tegral has reference to the co-ordinates.” 
January 6.—‘‘Some account of the Suez Canal in a letter ad- 
dressed to the president,” by J. F, Bateman, F.R.S. 
