SCIENCE ASSOCIATIONS. 



ASTRONOMICAL PHENOMENA. 47 





ruent of chemical science, taking the ground 

 that the present system of science-teaching was 

 faulty ; that more research should be executed 

 by the students. In the succeeding division 

 of his address he gave a very abstruse discus- 

 sion of chemical affinity and electro-chemical 

 relations of atoms, taking the ground that as a 

 rule a binary compound can not conduct elec- 

 tricity. 



Section C, devoted to geology, was presided 

 over by Prof. J. W. Judd, F. R. 8. His address 

 contained a general review of the remains of 

 geological periods. Interesting reference was 

 made to the solitary sample of the carbonif- 

 erous rocks ever discovered in Scotland, that 

 has recently been noted. 



Section D, devoted to biology, was presided 

 over by Prof. W. C. Mclntosh, M. D., LL. D. 

 He gave a most interesting address on phos- 

 phorescence of marine animals, referring it to 

 the following orders : Protozoa, coelenterates, 

 echinoderms, worms, rotifers, crustaceans, mol- 

 luscoids, mollusks, and fishes. The function 

 of phosphorescence in the animal world he 

 considered was still unexplained. Prof. Marsh, 

 of Yale College, read a paper in this section on 

 the size of brain in extinct animals. Sir John 

 Lubbock read papers on ants and bees and on 

 the intelligence of the dog, complaining that 

 we devoted our energies to teaching instead of 

 to understanding these animals. 



Section E, devoted to geography, was pre- 

 sided over by Prof. J. T. Walker, F. R. S. His 

 address included a long review of the British 

 surveys of India. Their immense extent, in- 

 cluding over 10,000 miles of actual spirit-level- 

 ing, was described. Several papers by officers 

 of these surveys were given in this section. 



In Section F, devoted to economic science and 

 statistics, papers were read on the subjects of 

 taxation and free trade. 



Section G, devoted to mechanical science, was 

 presided over by B. Baker, Inst. C. E. His 

 address, with its frequent references to Ameri- 

 can practice, was highly interesting. He de- 

 voted a part of it to the effects of intermittent 

 strains as a subject apt to be neglected in bridge- 

 construction. These strains in time would rupt- 

 ure almost any bar. The replacement of parts 

 in the trusses of the New York elevated rail- 

 roads, he said, was rendered necessary by this 

 species of deterioration. He then described, 

 more particularly, the construction of the Forth 

 Bridge, where almost everything is done by 

 hydraulic power. Of American bridge-practice 

 he said that the system of adhering in each 

 factory to a single type of bridge, and correct- 

 ing its defects, was the best. 



Section H, devoted to anthropology, was 

 presided over by Prof. Francis Galton, F. 0. S. 

 His address was on the subject of types and 

 their inheritance. It was a most curious in- 

 vestigation, reducing the conditions of type 

 variations as applied to hereditary stature to 

 the form of an equation. 



Among the committee reports, those on 



chemical nomenclature and on electric stand- 

 ards may be cited as especially important. At 

 a council meeting it was resolved to give a 

 hearty welcome to the American Association, 

 which may hold its meeting in 1887" or 1888 in 

 London. 



For the ensuing year, Prof. William Daw- 

 son, President of McGill University, Montreal, 

 was elected president. 



Reports of the papers are now appearing in 

 " Nature," of London. 



ASTRONOMICAL PHENOMENA AND PROGRESS. 

 Sun-Spots. For many years astronomers have 

 regarded the periodicity of sun-spot maxima 

 and minima as a proved fact, and the accumu- 

 lation of evidence derived from observation 

 extending over many years by Schwabe, Wolf, 

 and others seemed to warrant the conclusion 

 that a maximum of solar spots recurred regu- 

 larly about once in eleven years. So strongly 

 had this theory become intrenched that as- 

 tronomers looked confidently for the close of 

 another maximum in the year 1882. But they 

 were disappointed, for during 1883 -'85 there 

 appears to have been no abatement in their 

 number or magnitude. Suspicion, therefore, 

 necessarily attaches to the truth of the theory 

 of periodicity, and we are obliged to suspend 

 judgment until further observations have been 

 made. 



As to the time of the termination of the last 

 sun-spot maximum, observers differ. Mr. H. 

 C. Maine, of Rochester, N. Y., who has made 

 a study of the sun-spots for many years, places 

 it at about the middle of 1855, while another 

 observer carries its period back to the begin- 

 ning of the year. That it did not occur until 

 about the close of 1884 is generally conceded. 

 Frequently, during the early months of 1885, 

 spots upon the sun were, without difficulty, 

 seen by the naked eye if shielded with a smoked 

 glass. Such a one was seen on May 25, and, 

 on another occasion, two were visible at the 

 same time. 



Another conclusion that appears to have 

 been too hastily arrived at, is the connection 

 that was supposed to exist between the au- 

 rora and sun-spots. While this has sometimes 

 seemed to be verified, yet it is quite true that 

 many astronomers have been precipitate in de- 

 claring that there existed an intimate relation 

 between the two, with periodicity strongly 

 marked that is to say, that sun-spot maxima 

 and minima, and the maxima and minima of 

 the aurorae, occurred simultaneously. The fact 

 that, during the just-past prolonged maximum, 

 there was a minimum of the aurorse, militates 

 against this hypothesis, or, it may be, against 

 any connection whatever between the two 

 phenomena. 



Photographing the Solar Corona in the Absence of 

 an Eclipse. -Had Dr. Huggins made public dec- 

 laration of having photographed a grain of 

 sand on the surface of the moon, or any other 

 ludicrous statement, the announcement would 

 not have been received with greater increduli- 



