ii8 



NATURE 



[March 25, 1909 



SOCIETIES AND ACADEMIES. 

 London. 

 Royal Society, March i8.— Sir Archibild Geikie, K.C.B., 

 president, in the chair. — An attempt to detect some electro- 

 optical effects : Prof. H. A. Wilson. The paper contains 

 a description of some experiments made with the object 

 of detecting possible effects due to electric and magnetic 

 fields and moving matter on the velocity of propagation of 

 light in glass. The results obtained were negative, but it 

 seems worth while to publish a short account of the experi- 

 ments. The optical part of the apparatus is a simple form 

 of interferometer, which proved very easy and convenient 

 to work with. It consists of a square glass frame made 

 up of glass bars of square cross-section, cemented together 

 with Canada balsam. — The influence of their state in 

 solution on the absorption spectra of dissolved dves : Dr. 

 S. E. Sheppard. In the aqueous solutions of certain dye- 

 stuffs — isocyanines, pinacyanols, cyaninc — the dye is present 

 partially or wholly in colloid solution, and the absorption 

 spectrum is quite different from that of the true solution. 

 The influence of various agencies, as heat, acid and alkali, 

 electrolytes on the absorption was examined quantitatively. 

 In other dye solutions the change from true solution to 

 the, colloid state is accompanied by broadening and diffusion 

 of the absorption curve, consequent on the increase in 

 number and size of the colloid particles. Deviations from 

 Beer's law result. The state of dyes in solid media is 

 comparable with that in liquid, and the absorption spectrum 

 is similarly affected. The absorption of A number of dyes 

 by membranes was studied. The solution of dves appears 

 to be a combined process of disaggregation of the solute, 

 accompanied by a progressive combination with the solvent. 

 If the same stage of solution is attained in different 

 solvents, the absorption maxima are displaced according 

 to Kundt's law. — The ferments and latent life of resting 

 seeds.: Jean White. The resting seeds of cereals such as 

 wheat, maize, barley, oats, and rye all contain diastatic, 

 fibrin-digesting, and ereptic ferments in appreciable 

 amount. These ferments retain their activity without 

 appreciable change in stored dry seeds for twenty or more 

 years, that is, long after the power of germination has 

 been lost, which takes place in wheat after eleven to six- 

 teen years, barley eight to ten years, oats five to nine 

 years, maize and rye more than five years. No relation 

 was noted between the vitality of seeds and the persistence 

 of enzymes in them, but since the enzymes persisted longer 

 than Jhe power of germination, the question as to whether 

 germination could take place in the absence of any pre- 

 existent enzymes remains to be answered. In ■ any case 

 no otherwise non-germinable seeds could be excited to 

 germination by the addition of any kind of enzyme, and 

 where the germination was feeble the addition of enzymes 

 usually lowered the percentage germination and often 

 delayed germination also to some extent. The erepsin 

 appears to be more abundant than the pepsin, but other- 

 wise in the cases of all three ferments greater differences 

 are shown between different samples of the same age than 

 between different seeds, or between the same seeds of vary- 

 ing ages. Pepsin appears, however, to be more abundant 

 in rye than in any other cereal, and is almost absent from 

 maize. Dry oats, barley, and wheat can in part resist a 

 temperature of 99° C. to 100° C. for 1-4^ hours ; after six 

 hours' exposure all are killed, but the ferments are 

 apparently unaffected. All the ferments are destroyed after 

 an hour's dry heat at 130° C. to 131° C. The pepsin 

 appeared to be least (one hour at 124° C), the erepsin 

 more (one hour at 124° C. to 128° C), and the diastase, 

 especially of barley, most resistant to dry heat (one hour 

 at 124° C. to 131° C). Two days' exposure to liquid air, 

 although it delays the subsequent germination, and may 

 also decrease the percentage, did not absolutely destroy any 

 of the seeds tested, and did not appreciably affect the 

 ferments in any of the cereals. The drv diastase of barlev 

 IS therefore able to withstand a range of temperature of 

 200° C. to —130° C. : it is therefore thermally a highly 

 stable chemical compound. Many seeds, including all 

 cereals, give off appreciable quantities of carbon dioxide 

 when stored in the air-dried condition, but others show no 

 signs of respiration whatever. The respiration of air-dried 

 wheat is especially pronounced, but in practically all cases 

 NO. 2056, VOL. Sol 



every sign of respiration ceases when the seeds are 

 moderately desiccated, although in the case of large seeds 

 like maize minute traces of carbon dioxide may continue to 

 escape for a time. 



Geological Society, February 19. — Annual general 

 meeting. — Prof. W. J. Sollas, F.R.S., president, in the 

 chair. — -Anniversary address : Prof. W. J. Sollas. The 

 president dealt with the question of time, considered in 

 relation to geological events and to the development of 

 the organic world, referring, first of all, to recent evidence 

 in proof of the extreme rigidity of the interior of the 

 earth. He remarked that Mr. Strutt's method of 

 estimating the age of sediments by reference to their 

 radio-active constituents was of great promise, but a long 

 series of concordant observations would be required to 

 inspire absolute confidence in its results. Prof. Joly's 

 method of determining the age of the ocean, based on the 

 ratio of the amount of sodium which it contained to that 

 annually contributed to it by rivers, was subjected to a 

 detailed analysis, in the course of which it was pointed 

 oiit that the sodium contained in river-water existed chiefly 

 as sulphate or chloride, though theoretically it should be 

 in the state of carbonate. The origin of the chlorine was 

 manifold ; some vi'as traced to salts borne by the winds- 

 from the ocean, some to supplies from ancient desert-lakes 

 and some to juvenile waters escaping as hot springs or 

 impregnating the vadose waters underground. The prob- 

 able limits for the age of the ocean were 80 to 170 millions 

 of years. An examination of the sedimentary series, where 

 developed to their maximum thickness, gave a period of 

 35 millions of years, on the assumption that deposition 

 had proceeded at a rate of i foot in a century. Explana- 

 tions of the discrepancy were suggested, and it was pro- 

 posed to divide stratigraphical time into two moieties, 

 each of 40 millions of years' duration. The earlier or pre- 

 Cambrian moiety was termed the Protseon, the latter, or 

 post-Cambrian, the Neatson. Using the scale of i foot 

 in TOO years as a rough chronological measure, it was 

 applied to illustrate the rate of evolution in the case of 

 the Equidae and the chief varieties or soecies of man. 

 Though relatively rapid, when considered in connection 

 with some other groups of organisms, this was shown to 

 be so slow, when measured in terms of years, that per- 

 ceptible differences in a linear ancestral series would have 

 required tens of thousands of vears for their production. 



February 24. — Prof. W. J. Sollas, F.R.S., president, in 

 the chair. — Pala;olithic implements, &c., from Hackpen 

 Hill, Wintcrbourne Bassett, and Knowle Farm Pit (Wilt- 

 shire) : Rev. H. G. O. Kendall. Implements are described 

 from the localities mentioned in the title. Trimmed stones 

 of eolithic nature were obtained from fields ploughed in 

 Drift-gravcis, together with abraded Upper Greensand 

 chert, quartzke-pebbles, and small flints. Most of the 

 flaked stones were found in shallow pits excavated in 

 Drift-clay, exposed at the edges of the larger hollows. 

 The implements are unabraded, abraded, and striated ; 

 evidently some are in situ, others were brought with the 

 Drift. The implements are referred to the Chcll^en period. 

 While implements and flakes are numerous on the top of 

 Hackpen Hill as compared with trimmed pieces, yet at 

 Wintcrbourne Bassett plain implements and flakes are 

 scarce, while trimmed pieces are numerous. Many of the 

 latter have been re-chipped, and arc of later date. Imple- 

 ments of at least three Palaeolithic periods are found at 

 Knowle. — The Karroo system in northern Rhodesia, and 

 its relation to tHe general geology : .'\. J. C. Molyneux. 

 In 1903 the author described deposits, that have since 

 been recognised as of Karroo age, in southern Rhodesia. 

 Here he traces their extension across the Zambesi, where 

 their boundary follows the foot of the line of escarpments 

 that divide the plateau from the low-lying regions of the 

 Zambesi Valley. Karroo deposits also form the floor of 

 the trench-like valleys of the Luangwa. Lukasashi, and 

 Lusenfwa (or Luano), the walls of which are of rock- 

 gneiss, schist, and granite. The Luano Valley Is described, 

 and the Lusenfwa and Molongushi rivers are followed in 

 their courses across the plateau-plains. The Karroo de- 

 posits are grouped into basal conglomerates. Coal- 

 measures, Upper Matobola beds, and escarpment series. 

 In the Luano \^alley, the conglomerates are made up of 



