May 27, 1875J 



NATURE 



n 



been found bearing evidence of having been cut or perforated 

 by instruments belonging to the polished stone age. M. Broca, 

 in describing the crania submitted to his notice by M. Pru- 

 nieres, draws attention to a similar condition in a skull sent to 

 him by Mr. Squier, and taken by the latter from an ancient Peru- 

 vian tomb, in which a square opening had been made, evidently 

 by a saw, and probably a few days before death ; and he men- 

 tions that among the Kabyles and other African tribes trepanning 

 is resorted to in the present day for comparatively unimportant 

 diseases, while Hippocrates refers to the process as one esta- 

 blished in his time among the Greeks. M. Broca does not, 

 however, assume that cranial perforations among primitive races 

 in Europe had any connection with surgical processes, but is 

 rather disposed to assume them to have been the result of certain 

 obligations of religion.— M. J. de Baye describes circumstan- 

 tially the caverns and recesses, amounting to more than one 

 hundred, which he has recently discovered and explored in the 

 Valley de Petit-Morin, in Marne. — M. Bertrand has presented 

 the Society with a cast of a reindeer horn, on which is distinctly 

 traced with a flint instrument the figure of a reindeer grazing, 

 which was found at Thainghen, near Lake Constance. — MM. 

 de Quatrefages and Hamy, in oflfering their colleagues the second 

 edition of their great work on "Crania Ethica," which is en- 

 tirely devoted to the consideration of the Cro-Magnon race, 

 entered into an exposition of their views in regard to the rela- 

 tions existing between the Troglodytes of Perigord and certain 

 southern races, including not only the Basques, but Kabyle tribes 

 from the Beni-Menasser and Djurjura regions. 



SOCIETIES AND ACADEMIES 

 London 



Mathematical Society, May 13. — Prof. Cayley, F.R.S., 

 vice-president, in the chair. — The Rev. C. Taylor read a paper 

 on some constructions for transforming curves and surfaces. 

 The basis of the paper was a neglected work on conic sections, 

 •' which for originality and thorouj;hness is in its own special de- 

 partment unsurpassed." The author was G. Walker, F.R.S. , 

 of Nottingham, and his work appeared in 1794. The tedious- 

 ness of the style may account for the fact that the work was not 

 appreciated. Dr. Hirst and the Chairman made some remarks 

 on the paper. — Mr. J. W. L. Glaisher communicated some notes 

 on Laplace's coefficients. — A short paper by Mr. Harry Hart, 

 on a linkwork for describing sphero-conics and sphero-quartics, 

 was taken as read. 



Chemical Society, May 20. — Prof. Abel, F.R.S., pre- 

 sident, in the chair. — Mr. A. H. Smee read some notes on 

 milk in health and disease. From the results of numerous 

 experiments he finds that when cows are fed on sewage grass 

 alone the milk soon goes putrid, and the butter made from 

 it is soft, and rapidly becomes rancid. He also noticed the 

 outtreaks of typhoid which had occurred in various places 

 owing to sewage water having been used to cleanse the dairy 

 utensils or to reduce the quality of rich milk to the lowest 

 standard permitted by law. Along and interesting discussion 

 followed, after which Mr. W. H. Deering read a paper on some 

 points in the examination of waters by the ammonia method, 

 in which he proposes certain modifications to facilitate the 

 application cf the Nessler test and eliminate incidental errors. 

 There was also a ccmmunicatiun from Prof. H. Howe on some 

 Nova Scotian Triassic Trap minerals. 



Geological Society, May 12.— John Evans, V.P.R.S., pre- 

 sident, in the chair, — Ihe following communications were read. 

 — Notes on the occurrence of Eozoon catiadtnse at Cote St. 

 Pierre, by Principal Dawson, F. R. S. The author commenced 

 by describing the arrangement and nature of the deposits con- 

 taining Eozoon at the original locality of Cote St. Pierre on the 

 Ottawa River. The Eozoal limestone is a thick band between 

 the two great belts of gneiss which here form the upper beds of 

 the Lower Laurcntian. Eozoon is abundant only in one bed 

 about lour feet thick ; but occasional specimens and fragments 

 occur throughout the band. The limestone contains bands and 

 concretions of serpentine, and is traversed by veins of chi7Solite ; 

 the former an original part of the deposit, the latter evidently of 

 subsequent formation. A thin section, 5^ inches in depth, 

 showed ; (l) Limestone with crystals of dolomite and fragments 

 of Eozoon ; (2) Fine-grained limestone, with granules of serpen- 

 tine, casts of chamberlets ot Eozoon and of small Foraminilera ; 

 (3) Limestone with dolomite, and containing a thin layer of 



serpentine ; (4) Limestone and dolomite with grains of serpentine 

 and fragments of supplemental skeleton oi Eozoon ; (5) Crystal- 

 lised dolomite, with a few fragments of Eotoon in the state of 

 calcite ; ( 6) Limestone containing serpentine, as No. 2. The 

 author criticised some of the figures and statements put forward 

 by Messrs. King and Rowney, and noticed two forms of Eozoon, 

 which he proposed to regard as varieties, under the rames of 

 minor and acervulina. He stated that fragments of Eozoon, 

 included in dolomitic limestones, have their canals fille i v^'ith 

 transparent dolomite, and sometimes in part with calcite. In 

 one specimen a portion was entirely replaced by serpentine. 

 The author called particular attention to the occurrence of ser- 

 pentinous casts of chamberlets, single or arranged in groups, 

 which resemble in form those of the Globigerine Foraminifera. 

 These may belong either to separate organisms or to the acer- 

 vuline layer of the Eozoon ; the author proposes to call them 

 Archaospherina, and describes them as having the form and 

 mode of aggregation of Globigerina, with Ihe proper wall of 

 Eozoon. The author discussed the extant theories as to the 

 nature of Eozoon, and maintained that only that of the in- 

 filtration of the cavities of Foraminiferal structure with ser- 

 pentine is admissible. He particularly referred to the resem- 

 blance of weathered masses of Eozoon to Stromatoporoid corals. 

 — Remarks upon Mr. Mallet's theory of volcanic energy, by the 

 Rev. O. Fisher, F.G.S. Mr. Mallet's paper, read before the 

 Rojal Society in 1872, was discussed by the author seriatim as 

 far as it seemed open to criticism. With respect to the condition 

 of the earth's interior, whether it be rigid or not. Sir W. Thom- 

 son's arguments for rigidity were referred to, and geological diffi. 

 culties in accepting his conclusions suggested. Mr. Mallet's 

 views regarding the formation of oceanic and continental areas, 

 that they have on the whole occupied nearly the same positions 

 on the globe at all periods from the very first, were objected to 

 on the ground that all continental areas with which we are 

 acquainted are formed of water-deposited rocks, and that there- 

 fore those areas must at some time have been sea-bottoms ; and 

 if these wide features have not occupied the same positions which 

 they now do from the very first, Mr. Mallet's explanation fails, 

 that they were caused by unequal contraction when the crust 

 was first permanently formed and thin. It was also shown that 

 the theory of unequal radial contraction cannot account for the 

 difference of elevation between continental and oceanic areas 

 upon reasonable assumptions. For if we consider the crust to 

 have been 400 mUes thick (which cannot be considered thin), 

 and to have cooled from 4000° F. to zero (a most extravagant 

 supposition), then, if the crust had contracted one-tenth more 

 beneath the oceanic area than it had done beneath the conti- 

 nental, we should only get a depression of one mile for the 

 oceanic area, using Mr. Mallet's mean coefficient of contraction. 

 The main feature of Mr. Mallet's theory was then discussed, viz., 

 that " the heat, from which terrestrial volcanic energy is at pre- 

 sent derived, is produced locally within the solid shell of our 

 globe, by transformation of the mechanical work of compression 

 or crushing of portions of that shell, which compressions and 

 crushings are themselves produced by the more rapid contraction 

 by cooling of the hotter material of the nucleus beneath that 

 shell, and the consequent more or less free descent of the shell 

 by gravitation, the vertical work of which is resolved into tan- 

 gential pressures and motion within the shell." Mr. Mallet's 

 mode of estimating the amount of heat derivable from crushing 

 a cubic foot of rock was explained, and it was accepted as a 

 postulate, that the heat developed by crushing one cubic .foot of 

 rock would be sufficient to fuse O"lo8 of a cubic foot of rock ; or, 

 in other words, that it would require nearly the heat developable 

 by crushing ten volumes to fuse one. Mr. Mallet considers that 

 the heat so developed may be localised. But Mr. Fisher inquires 

 why, since the work is distributed equally with the crushing, the 

 heat should not be so also ; and, since no cause can be assigned why 

 one portion of the crushed portion of rock should be heated more 

 than the rest, assumes that all which is crushed must be heated 

 equally. In short, he is of opinion that if Mr. Mallet's- theory 

 were true, the cubes experimented upon ought to have been 

 themselves fused. After paying a just tribute of admiration to 

 Mr. Mallet's elaborate and highly important experiments upon 

 the fusion and subsequent contraction of slags, the author re- 

 marked upon Mr. Mallet's estimate of the probable contraction 

 from cooling of the earth's dimensions, showing that it had been 

 based on untenable assumptions. (The author of the paper, 

 however, holds that the contraction of the dimensions of the 

 globe has been greater than mere cooling will account for.) 

 Upon the concluding portions of Mr. Mallet's paper, in which 



