452 



NATURE 



[Oct. I, 1874 



SECTION B— Chemical Science 



Oil l!ic Specific Volumes »f certain Liquids, by Prof. Thorpe. — 

 Kopp found that the specific volumes of certain elements varied. 

 Thus, the specific volume of oxygen " within the radicle" = I3'2, 

 "without the radicle" = 7'S ; of sulphur, " within the radicle " 

 = 28'6, " without the radicle " = 22'6. "Within the radicle" 

 was defined as meaning an instance where the oxygen or sulphur 

 atom is united Vjy hiv bonds to the binding element, while upon 

 " without the radicle " it is united by only one bond. Kopp 

 announced that memliers of tlie same chemical family have iden- 

 tical specific volumes. The author determined the specific 

 volumes of vanadyl trichloride, VOCI3, and phosphoryl tri- 

 chloride, POCI3, and found in the former case that the specific 

 volume = io6'5, while in tlie latter it = loi'5. Kopp's law 

 does not therefore hold in this instance. The following examples 

 also show that as the atomic weight increases the specific volume 

 also increases : — 



SiCIj specific volume = 1211 



TiClj ,, ,, = 125T 



SnClj , „ =132-4 



Another of Kopp's deductions is that isomers have the same 

 specific voUime ; but the author found a difference between the 

 specific volumes of ethyl-amyl and heptane, both of which are 

 expressed by the formula CjHj,; ; in the former case the number 

 was 1 62 '25, while in the latter it was I57'34. The author also 

 determined the specific volume of the compounds TCIj — 937, 

 POCI3 — ioi'5, and rSCl, = 116-3. Now, 101-5 — 93'7 = 

 7'8 ; that is to say, the specific volume of oxygen in POCI3, is 22 -6, 

 hence it is without the radicle in this compound. So also 

 Il6"3 — 93-7 = 22-6; that is, the specific volume for sulphur 

 "without tlie radicle." Hence the structural formula of these 



CI 

 two substances POCK and PSCIs will be | land 



CI— P— O— C 

 CI 



I respectively ; that is, in each case phosphorus is 



CI— P— S-Cl 

 most probably a triad, not a pentad element. 



On the Dissoeialion of Nitric AciJ, by Messrs. Braham and 

 Gatehouse. — Nitric acid when passed through an ordinary clay 

 pipe at varying temperatures is split up : at the temperature of 

 molten tin 2-io per cent, is decomposed ; at the temperature of 

 molten lead 22 to 23 per cent, is decomposed ; when the clay 

 pipe is heated with gas 71-72 percent, is decomposed, while 

 when heated with charcoal 834 per cent, is decomposed. The 

 gases evolved consist of oxygen, nitrogen, and nitrous oxide ; the 

 proportion of these gases it has been found very difficult to deter- 

 mine accurately. Tlie following probably represents the reaction 

 which takes place at minimum temperatures : — 



SHNO3 = 4NO., -h 4H„0 -I- N„0 -^ Nj + Oil. 

 When glass bulbs are partially filled with nitric acid and exposed 

 to direct sunlight, the acid is decomposed, the amount varying 

 with the time and intensity of the light ; the decomposition is 

 brought about by the violet end of the spectrum. If the bulbs 

 are entirely filled with nitric acid, no decomposition ensues. 

 After some time the decomposition ceases ; this is due to the 

 formation of nitrous acid, and if this is expelled by boiling, the 

 decomposition again proceeds. If pure nitric acid be boiled, 

 even to dryness, no decomposition takes place, but if the acid 

 contains nitrous acid, then this latter is dissociated. 



On the Kepiacenient of Organic Matter !>y Siliceous Deposits in 

 the process of Fossilisation, by Dr. Carpenter, F.R.S. — The 

 author described several cases in which the internal casts of 

 Foraminifera were found, consisting of silica, generally as silicate 

 of iron. This process is now going on at the ordinary sea- 

 bottom. Fragments of the spines of Echirue, which originally 

 contained protoplasm, have been found, in which the organic 

 matter has been entirely replaced by silica, thus forminj; exact 

 siliceous models of the animal matter. In some cases the 

 siliceous deposit has preserved the exact form of thin tubes less 

 than i-iooooth of an inch in diameter. The author supposed that 

 during the gradual decay of the animal matter there had occurred 

 a simultaneous deposition or substitution of siliceous matter in 

 its stead. 



Oti the Silicified Rock of Lough Neagh, by Prof. Hodges. — The 

 water of I-ough Neagh was found to contain only 12-95 grains of 

 solid water per gallon ; of this, 10-6 grains consisted ot mineral 

 matter, while 2-35 grains of organic matter were present. Of 



the total mineral salts a very small quantity only — less than 

 I grain per gallon — consisted of ferric oxide. Samples of 

 petrified wood were also examined : these contained on an 

 average about 87 per cent, of silica, and a very small percentage 

 of iron. 



On a Self-registering Apparatus for measuring the Chemical 

 Intensity of Light, by Prof. Roscoe, F.R.S. — In this communica- 

 tion the author described his already well-known self-registering 

 photo-chemical apparatus. 



On certain Abnormal Chlorides, by Prof. Roscoe, F.R.S. — The 

 author drew attention to some of the chlorides of vanadium, 

 tungsten, uranium, and sulphur. The highest chlorides which 

 we have been able to obtain of these elements generally do not 

 correspond with the highest oxides ; thus, although we know of 

 the oxides VoOj, we know of no higher chloride than VCl ,, and 

 even this chloride is easily decomposed into VCI3 and free 

 chlorine. Although the oxide of tungsten, WO3 is stable, yet 

 the corresponding chlorine WCI5 is very ready to split up into 

 WCI5 and free chlorine. So also UO3 is a well-known oxide of 

 uranium, yet until lately UCI4 v/as the highest known chloride. 

 The author has recently succeeded in preparing the penta-chloride 

 UCI5, which occurs as a light brown powder, and also as darker 

 acicular crystals. Again, we have SOj and SO3, but it is only 

 very lately that SCI4 has been obtained, and the compound is so 

 unstable as to undergo"dissociation at very low temperatures. — 

 Dr. Debus suggested that the equivalency of many of the 

 elements depends upon the element or elements with which 

 they are i"i icd, and that hence these and other anomalous 

 rfsul.s. — The President remarked that he did not see why 

 we should not expect to meet with examples of change of 

 atomicity ; that if we alw.ays found elements exhibiting an 

 even, or always an odd number of atomicities, this was very 

 remarkable, and called for explanation, but that we should not 

 be surprised to meet with exceptions to the rule ; indeed, that we 

 could form no distinct physical idea of what we mean by " bonds 

 of atomicity. " He remarked that we cannot well use oxygen as 

 a measure of atomicity, from the tendency which it so often exhibits 

 of running into chains. 



SECTION D— Biology 

 Dei'arthent of Zoology and Botany 



Dr. Moore called attention to a monstrous state of Megacar- 

 pica, and also to a monstrous state of Sarracenia : after which 

 he exhibited specimens of grafted roots of mangold wurzel, illus- 

 trating the tr.ansniission of special characters from the graft to 

 the stock. 



Mr. E. R. Lankester read a paper On the genealogical im- 

 part of the extirnal shell of MoUusca, in the course of « hich I.e 

 referred to what has been called the recapitulation hypothesis, 

 according to which all living things in their development present 

 a rapid series of pictures or dissolving views of their ancestors, 

 arranged in historical order. Applying this to the Iiuman race, 

 he said that the earliest commencenient of a human being was a 

 small speck of protoplasm of mucus-like consistency, such as 

 existed in ponds. A later stage exhibited him as a small sac, 

 composed of two layers of living corpuscles, which he inherited 

 from polyp-like ancestors, and was to-day seen in polyps. Still 

 later he was an elongated creature, with slits in the side of the 

 neck, which, like the gill-slits of a shark, he inherited from a 

 shark-like ancestor. Six months after birth the child continued 

 to inherit qualities from its ancestors, viz., from those which 

 crawled on four legs ; and at a later period certain irrepressible 

 tendencies made it clear that qualities were inherited from climb- 

 ing and shrieking animals. Mr. Lankester then went into an 

 elaborate description of certain molluscs with a view of showing 

 that the pen of the cephalopod is homologous with the shell of 

 the lower Mollusca. 



Prof. Huxley thought that the position had been well cst.-ib- 

 lished. Mr. Lankester's attempt to reduce to one form the 

 immense variety of shells in molluscous animals was exceedingly 

 important. 



Dr. Carpenter also said that he was almost prepared to receive 

 the conclusion at which Mr. Lankester had arrived. 



Dr. M. Foster added his testimony to the value of Mr. Lan- 

 kester's observations, and said that part of the work accom- 

 plished was due to the establishment of the zoological station at 

 Naples. 



Mr. W. Archer read a paper On a new form of Protozoa, 



