104 



NATURE 



[December 2, 1897 



specially studied the bacterial flora of canned clams and lobsters 

 which have broken down, or, in other words, been imperfectly 

 preserved. In every case where " spoiling " had occurred, bacteria 

 were present in large numbers, whilst in no instance were any 

 -discovered in sound cans. Sometimes only a single variety, or 

 a pure culture of a particular microbe, was found in unsound 

 -cans, but usually the latter contained a mixture of several 

 species. Nine different bacteria were selected and isolated for 

 subsequent study, both as regards their macroscopic and micro- 

 scopic appearances ; two of these were cocci, the remainder 

 bacilli forms. These bacteria were afterwards inoculated into 

 the contents of sound cans, with the result that the latter in- 

 variably decomposed, whilst experiments were also made to 

 ■test the method of applying heat to canned articles which would 

 most effectually destroy the chances of these micro-organisms 

 surviving and spoiling the contents. An account of the 

 numerous experiments carried out by the authors on this highly 

 important commercial side of the inquiry will be published 

 later ; meanwhile their investigations go to show that, given a 

 jproper control of the temperature, it is possible to preserve 

 •clams and lobsters with absolute certainty, and in a more perfect 

 •condition than has hitherto been possible. 



Thk Journal de Physique for November contains a specially 

 good collection of abstracts of physical papers, in addition to 

 an important paper by M. Gerrit Bakker, on the thermodynamic 

 properties of liquids with simple molecules, and a note by M. 

 J. Schurr, on electric resistance and self-induction. 



From Mr. F. W. Frankland, of New York, we have received 

 several papers on the " Theory of Discrete Manifolds," dealing 

 with the postulates of Euclidian geometry and their hypothetical 

 •counter-propositions, space-curvature, and the geometric axioms. 

 Almost concurrently with these essays, Signor G. Veronese gives 

 n the Atti del Lined a disquisition on the postulate of con- 

 tinuity, in which he arrives at certain conclusions contrary to the 

 •views of Schonflies. 



Some ten years ago, Weber discovered that a heated body 

 ibegins to emit visible radiations at a lower temperature than 

 ■that at which it exhibits the well-known glow of red heat. 

 This " grey-glow," as it has been termed, has been investigated 

 from a physiological standpoint by Herr O. Lummer {Annalen 

 ■der Physik und Che>nie, 62). According to the author's theory 

 the observed appearances are due to the different susceptibilities 

 of the rods and cones of the retina to light of varying intensity, 

 'the grey-glow being perceptible only to the rods, while the red- 

 .glow stimulates the cones. It is proposed to make observations 

 of the lowest temperature at which luminosity occurs. Herr 

 Lummer expresses the view that this temperature depends in 

 some degree on the area of retinal surface exposed to the 

 radiations. 



From a series of investigations on the temperature-coeffi- 

 cient of the potential of the calomel electrode [Proceedings of 

 ihe American Academy of Arts and Sciences, xxxiii. No. i), 

 Mr. Theodore William Richards draws the following conclu- 

 sions : (a) The temperature-coefficient increases with the dilu- 

 'tion of the electrolyte ; {b) the kation of the electrode influences 

 the result by affecting the degree of dissociation of the chloride in 

 solution ; (c) both of these effects may be approximately computed 

 •by a simple logarithmic formula based upon Nernst's hypothesis ; 

 (d) the accuracy of the results is, however, affected by at least 

 one important modifying influence, the " catalytic " decomposi- 

 tion of mercurous chloride into mercuric chloride and mercury ; 

 i^e) this side reaction is responsible for the slight inconstancy of 

 ■the normal calomel electrode ; (/) the " decinormal electrode " 

 is much more uniform in its behaviour than the normal, and 

 lience for some purposes might be a more useful means of 



NO. 1466. VOL. 57] 



measuring potential differences ; [g) hydrochloric acid and 

 ammonic chloride are anomalous in their behaviour. 



Among recent contributions to systematic botany are " North 

 American Lemnaceee," by Mr. R. C. H.. Thompson, all four 

 genera which comprise the order being represented ; and 

 "Contributions to the Flora of Queensland," by Mr. F. M. 

 Bailey, in which two new species of Nepenthes are described 

 and figured. 



The Botanical Gazette states that another botanical journal 

 has entered the field as a popular magazine in America. The 

 Asa Gray Bulletin has ceased to be the organ of the Agassiz 

 Association, and has entered upon a larger field. It will in 

 future be published monthly, at Washington, D.C. 



The last issue (Appendix i., 1898) of the Kew Bulletin of 

 Miscellaneous Inforviation consists of a list of seeds of hardy 

 herbaceous plants, and of trees and shrubs (mostly ripened at 

 Kew during 1897), available for exchange with colonial, Indian, 

 and foreign botanic gardens, as well as with regular corre- 

 spondents of Kew. 



Two useful publications recently received from the U.S. 

 Department of Agriculture (Division of Vegetable Physiology 

 and Pathology) are "The Bermuda Lily Disease," by Mr, 

 A. F, Woods, attributed by the author to a variety of causes, 

 chiefly negligent horticulture ; and " Notes on the Grasses and 

 Forage Plants of Iowa, Nebraska, and Colorado," by Prof. 

 L. H. Pammel, illustrated by a number of excellent woodcuts. 

 Dr. E. F. Smith sends us a reprint from the Centralblatt fUr 

 Bakteriologie, Parasitenkunde, und Infektionslirankheiten (in 

 English), on Pseudomonas campestris, the cause of a brown rot 

 in cruciferous plants caused by a Schizomycete, hitherto known 

 as Bad llus campestris. Having only a single long polar flagel- 

 lum, the author regards it as belonging to Migula's genus 

 Pseudomonas. The life-history and effects of the parasite are 

 described in detail. 



The second edition of a series of " Laboratory Tables for 

 Qualitative Analysis," drawn up by the demonstrators in chem- 

 istry of the Owens College, Manchester, has been published by 

 Mr. J. E. Cornish. The tables show in a systematic way, how 

 the student should proceed to examine a solid substance, to make 

 a preliminary examination for acids, to examine acid mixtures, 

 or make a preliminary examination of an organic substance. 

 Following these instructions are tables for the various groups 

 of metals. Each schedule or table occupies one sheet (except 

 the two first tables, which cover two sheets each). The tables 

 are thus handy for use in chemical laboratories where simple 

 analysis has to be carried on, though the demonstrators them- 

 selves would often prefer to give the laboratary work a more 

 educational value if they were at liberty to do so, or if time 

 enough was allowed them. Where a course of qualitative 

 analysis is a part of the curriculum, and the demonstrator has 

 thirty or forty students to look after, the tables should be found 

 useful, for they will save the student from worrying his instructor 

 with unnecessary questions. 



The additions to the Zoological Society's Gardens during the 

 past week include a Common Marmoset (Hapale jacchus) from 

 South-east Brazil, presented by Mr. G. Willison ; an African 

 Brush-tailed Porcupine {Atherura africana) from West Africa, 

 presented by Captain W. C. Woollett ; a Flat-backed Terrapin 

 (Cyclemmys platynola) from Johore, Malay Peninsula, presented 

 by Mr. S. S. Flower; a Leopard Tortoise {Testudo pardalis) 

 from South Africa, presented by Miss E. Harold ; a Hawk's- 

 billed Turtle {Chelone imbricata) from the East Indies, two 

 Scorpion Mud Terrapins (Cinosterjton scorpioides) from Guiana, 

 eleven Dumeril's Grieved Tortoises {Podocneinis duneriliana) 

 from South America, presented by Dr. J. Bach ; a Smooth 



