518 GJironicles of Science. [Oct., 



means of transport, — the reason suggested for the expected refusal 

 being the war which is at present devastating France. We can 

 scarcely believe, however, that the Government will abide by this 

 resolution. Eemembering that some of the most important of those 

 researches which adorn the annals of English science have been 

 prosecuted under Government protection, and with Government 

 aid, while England has been in the throes of deadly warfare — nay, 

 when the very existence of England has been at stake — we refuse to 

 believe that the mere risk of war should cause our Government 

 to refuse a single ship in aid of scientific observations of extreme 

 interest and importance. 



Unfortunately, the mere report of such a probability has sufficed 

 to check the process of preparation ; and despite our confidence that 

 England is not destined to suffer shame in this matter, we are com- 

 pelled to recognize the possibility that the only systematic observa- 

 tions of this important eclipse will be made by French astronomers 

 in Algeria. 



Further on will be found an account of the extent to which the 

 eclipse will be partially visible in this country. 



Dr. Zollner, known as one of the most successful students of 

 solar physics, has been inquiring into the evidence which the form 

 and dimensions of prominences afford respecting the temperature 

 and physical condition of the sun. He points out that prominences 

 may be divided into two classes, the cloud-formed and the eruptive 

 prominences. Those belonging to the latter class are so obviously 

 due to real eruptive action that we may fairly refer them to the 

 same general cause as terrestrial eruptions, that is, to a difference 

 between the pressure in the region whence the erupted matter flows 

 and the pressure in the space into which that matter passes. But 

 this view requires us to believe that there is a barrier-layer (Tren- 

 nungscliiclit) by which one region is separated from the other — a 

 stratum limiting the compressed hydrogen below the chromosphere 

 from the free atmosphere of hydrogen which constitutes a propor- 

 tion of that envelope. 



Starting with this hypothesis, Dr. Zollner proceeds to apply the 

 mechanical theory of heat to determine the temperature of different 

 portions of the sun's globe. We see that the prominences are pro- 

 jected to a certain height, and we have therefore a means of de- 

 termining the force exerted in the propulsion of the compressed 

 hydrogen. The equations for this purpose are those resulting from 

 the law of Mariotte and Gay-Lussac, and those which are deduced 

 from the theory of heat. Certain assumptions have to be made, the 

 probability of whose truth depends on the interpretation of tele- 

 scopic and spectroscopic observations of the sun. 



Some of the results are of great interest, especially as, even 

 though the fundamental suppositions should be importantly in error, 



