88 



SCIENTIFIC NEWS. 



[July 27, 1888. 



&fojstract$ 

 of i^apetrjg, Hectureg, etc* 



NORTHERN INSTITUTE OF LITERARY AND 



SCIENTIFIC SOCIETIES. 

 The first meeting of this Association was held at Huntly 

 on the 14th inst. Mr. Charles Proctor read a paper 

 on the " Composition of the Atmosphere in the Early 

 Geological Epochs." He pointed out that while all 

 the solid and liquid portions of the globe were chemi- 

 cal compounds, the atmosphere was mainly com- 

 posed of two free elements, these being the remains 

 of the elemental gases out of which the earth had con- 

 densed. Water, probably one of the last combinations, 

 would, when first condensed, be exceedingly hot, and 

 would thus act with much greater force as a disintegrating 

 agent than in its present form, especially in presence of 

 much carbonic acid gas. Thus the character of such 

 rocks as granite, gneiss, and metamorphic rocks could be 

 accounted for. Mr. Proctor then proceeded to point out 

 that independently of this theory of the evolution of the 

 earth there was evidence of there having been much 

 more carbonic acid in the atmosphere at the close of the 

 Silurian and Devonian eras. Pointing out that coal was 

 only the remains of ancient forests, and that these could 

 only obtain their carbon from the carbonic acid gas in 

 the atmosphere, he gave figures showing that even the 

 workable coal known to exist in the world must have re- 

 quired 45 billions of tons of carbonic acid to produce it. 

 And this he reminded the meeting was only a small 

 proportion of the remains of actual vegetation now buried 

 in the earth's crust. Turning his attention next to animal 

 remains he pointed out that probably the bulk of all 

 limestone rocks were originally the shells of living 

 creatures, and that these had been enabled to leave such 

 remains only through the agency of the same carbonic 

 acid. At all events the great chalk formation of Europe 

 was such, and these he calculated, quoting Sir C. Ly all's 

 description of them, must have required 50 to 60 billions 

 of tons of carbonic acid gas, which, added to that from 

 the coal, gave at least 100 billions of tons — a quantity 40 

 times greater than is now found in the atmosphere, and 

 this was only a small portion of the whole quantity that 

 must at one time have been present. In such an atmos- 

 phere, even without the higher temperatures, disinte- 

 gration and deposition of new rocks must have gone on 

 at a much greater rate than in the present age. 



Dr. J. O. Wilson, Huntly, contributed a short paper 

 dealing with " Salmon Disease." The disease referred to 

 was the fungus disease, which has attracted so much 

 attention within the last ten years. It first assumed 

 serious proportions in the Eden, in Cumberland, in 1877, 

 and since that time has visited most rivers in the 

 United Kingdom. In the Deveron it was worst in the 

 autumn and winter of 1883-84; but has since abated. 

 Dr. Wilson then gave a resume of the character and 

 course of the disease, pointing out that it began on the 

 parts uncovered by scales, and afterwards spread to the 

 rest of the body, destroying large areas of tissue by 

 ulceration. The immense number of the spores that spread 

 the disease was also pointed out, and the consequent 

 helplessness of man in endeavouring to stamp out such 

 a disease, Nature's remedy, sea-water, being the best and 

 most efficacious, if the sufferer can only reach the healing 

 waters. 



SOUTH LONDON MICROSCOPICAL AND NATURAL 



HISTORY CLUB. 

 At the June ordinary meeting of this Club, the evening's 

 gossip was opened by the President, Mr. Frederick 

 Hovenden, who drew attention to the interesting 

 phenomena presented by a thin film of water under 

 the microscope. The film might be obtained by simply 

 breathing on the blade of a knife, when the steam would 

 condense and the disappearance of the water could be 

 observed with a half-inch power. As the globules 

 evaporated, they appeared to leap into the air, the actual 

 point of final disappearance, however, being difficult to 

 detect. Some curious questions as to molecular action 

 were raised by this experiment, as well as by those 

 which he suggested should be made in connection with 

 thin sections of iron. In testing this metal for commer- 

 cial purposes, a tension strain was used which caused the 

 iron before it broke to ribbon out with considerable heat. 

 Steel under a similar tension made a clear fracture with- 

 out thinning out and without heat, and this was remark- 

 able, as the tension required to break the steel was 

 greater than in the case of the iron. He believed that if 

 thin sections of iron were made, they would be found full 

 of pores, whilst in sections of steel there would be but 

 few. His theory was that the minute gaps were filled 

 with air, and that the effect of the intense tension was to 

 compress these spaces, thus generating the heat, which 

 was immediately taken up by the iron with a consequent 

 increase of temperature. 



Mr. Suffolk observed that some years ago Mr. Sorby 

 had worked out the subject of sections of iron and steel. 

 He had viewed them as opaque objects, having been 

 unable to obtain transparent sections, as the metal would 

 not hold together. Gold would, however, do so, and 

 transmitted light of a greenish tint. With respect to the 

 pond-life exhibited, Dr. Hudson had taken Brachionus as 

 the type of a rotifer, and a beautiful drawing of it was 

 given in his work, with an account of its anatomy. The 

 growing slide, Mr. Suffolk said, was not sufficiently used 

 by microscopical observers. If they would only take u 

 the life-history of a diatom, and trace it from its cradle to 

 its grave, many of the so-called species would be found 

 to be but different conditions of the same organism. 



Mr. Dadswell explained that the exhibits he had 

 brought to the meeting had all been collected in the 

 neighbourhood of Epping Forest, within an hour's ride 

 from the City. Volvox, stentors, corethra, brachionus, 

 and the more unusual forms, were easily obtained in the 

 locality he had visited. 



A specimen of Melicevta ringeus, from Clapham 

 Common, was exhibited by Mr. Neville, who stated 

 that within the last few years the water-life of the 

 Windmill Pond had considerably altered in character. 

 Some years ago the pond literally teemed with the 

 crowned rotifer, Stephanoccros eichornii. This had now 

 disappeared, but in its place the brick-making Melicerta 

 had sprung up, and might be obtained on the scanty 

 vegetation that had managed to survive the building 

 operations in the vicinity. 



Mr. Oakden gave some interesting particulars with 

 reference to the hydrachnidae. The specimen under his 

 microscope belonged to this species of water mite, and 

 was a female. Only those acquainted with the subject 

 were able to determine the difference of sex. The males 

 were fewer in number and of a pale colour. About 40 

 different species were known of these arrennui, but only 

 a small number were mentioned in the works of English 



