Febeuaey 5, 1897.] 



SCIENCE. 



219 



epoch in physiology. In 1848 appeared the 

 first volume of that book, ' Untersuchungen 

 ueber thierische Elektricitat.' In 1849 

 followed the first part, and in 1860 the 

 second part, of the second volume. It was 

 not simply a communication of new striking 

 facts and new methods ; it was an exhaus- 

 tive statement of the creation and comple- 

 tion of a new science, presented in a brilliant 

 style and in a language unusually clear and 

 full of life and force. His later contri- 

 butions to the physics of nerve and muscle 

 appeared mostly in the reports of the Berlin 

 Academy of Sciences, or in the Archiv fiir 

 Physiologic, of which du Bois-Reymond was 

 the editor. Among the fundamental facts 

 which were added by du Bois-Reymond to 

 physiology we have to mention, in first 

 place, the establishment and development 

 of the laws of the muscle current, the dis- 

 covery of the nerve current, the discov^ery 

 of the so-called negative variations in 

 muscle and in nerve, the discovery of the 

 electrotonus, etc., etc. Du Bois-Reymond 

 has devised and invented numerous impor- 

 tant scientific apparatus, many of which 

 are to be found in all well-equipped physio- 

 logical laboratories ; for instance, the in- 

 duction coil, the electric key, the non- 

 polarizable electrodes, etc., etc. Du Bois- 

 Reymond's name will live forever in the 

 science of physiology. 



Aside from his special scientific work, we 

 should not omit to mention the public 

 speeches (Reden) delivered by du Bois-Rey- 

 mond on many special occasions. In those 

 speeches, as a rule, an important subject 

 was treated in a classical style. They were 

 models of clearness and brilliancy, and 

 nearly every one of his speeches has been 

 an event in its time, and many of them 

 have been translated into all civilized lan- 

 guages. We need only to mention here the 

 following: 'Darwin versus Galiani,' 'Die 

 Lebenskraft,' ' Ueber die Grenzen des Na- 

 turerkennens,' with his ignorabimus, and 



'Die Sieben Weltrathsel.' He was as 

 forcible a speaker as a writer. And both 

 his pen and his speech have been employed 

 only for a fearless propagation of high 

 ideals and in defence of the rational princi- 

 ples underlying modern sciences. 



His last work was one of love. Shortly 

 before he died he finished reading the 

 proofs of his carefully prepared memorial 

 of his friend Helmholtz. 



S. J. Meltzek. 



CURRENT NOTES ON 3IETE0R0L0GY. 

 THE PLAGUE AND CLIMATIC CONDITIONS. 



The present outbreak of the plague in 

 India suggests certain considerations with 

 reference to the possible connection of its 

 occurrence with climatic conditions. While 

 it used to be thought that the plague could 

 not occur in the Torrid Zone, it is now known, 

 in view of outbreaks of the disease within the 

 tropics in Arabia and India, that this rule 

 does not hold rigidly. In Egypt the au- 

 tumn seems to be the season in which the 

 plague appears, and June the month in 

 which it dies out. In Europe, outside of 

 Turkey, the plague season has been sum- 

 mer and autumn. In India no direct con- 

 nection with the seasons could be detected 

 in the epidemics of 1815-21, the first out- 

 break concerning which we have trust- 

 worthy information, and of 1836-38. From 

 all the data at hand, the general conclusion 

 is that a moderately high temperature fa- 

 vors the development and extension of the 

 plague, but extremes of heat and cold are 

 unfavorable to its breaking out. Excep- 

 tions to this rule are many. For instance, 

 in the epidemic at Smyrna in 1735 the heat 

 was so excessive during the plague that 

 many of the people who left the town for 

 neighboring villages died of sunstroke on 

 the way, while in Roumelia, in 1737-38, the 

 plague continued in many places in which 

 the temperature fell at times to 3° Fahr. 

 Regarding the effect of atmospheric mois- 



