March 13, 1885.] 



SCIENCE. 



211 



eclipse is doubtless entitled to interest the 

 average observer but little ; however, it is quite 

 possible that the rapid development of the 

 means of eclipse research may in time lead to 

 the utilization of annular eclipses with quite the 

 same regularity that total eclipses are at the 

 present day observed. In so far as we have 

 learned, astronomers have made no prepara- 

 tions for observing this eclipse within the belt 

 where the annular phase is visible. 



The notion that an annular eclipse is an in- 

 different species of occurrence has certainly 



with the annular eclipse which occurs on Mon- 

 day next, when the moon's semi-diameter is 

 only one- thirtieth part less than the sun's — 

 the eclipse which is put down in the almanacs 

 as annular, only barely escapes being total. 

 It seems very possible that a strongly developed 

 corona might be observed on such occasions : 

 indeed, the experience of many observers who 

 have followed the corona after the total phase, 

 makes it quite probable. To be sure, the du- 

 ration of the annulus at such times is very 

 short; but, if the corona could be observed 



110' Longitude West from 9U' Greenwich. 



ANNULAR SOLAR ECLIPSE OF MARCH 16, 1885. 



been helped along by the deceptive way in 

 which these eclipses are almost always repre- 

 sented in astronomical treatises, where the 

 ratio of the semi-diameters of the sun and the 

 moon are unnecessarily out of proportion ; and 

 frequently that of the moon is drawn only three- 

 quarters that of the sun, thus giving the im- 

 pression that a very large proportion of the 

 total light of the sun is unextinguished at the 

 time and place of central eclipse. In point of 

 fact, the greatest breadth the annulus can have, 

 under the most favorable circumstances, is only 

 about a minute and a half of arc, or less than 

 one-tenth the semi-diameter of the sun at the 

 time; while not infrequently — as is the case 



on these occasions, we should be able to halve 

 the intervals of an observation as conducted 

 by the present methods at the times of total 

 eclipses only. 



THE ANNISQUAM SEASIDE 

 TORY. 



LA BORA 



We have in America two classes of sum- 

 mer schools of natural histoiy, — one in which 

 only original investigators are allowed to study 

 (Professor Agassiz's laboratory at Newport, the 

 Fish-commission laboratory at Wood's Holl, 

 and the Johns Hopkins laboratory at Beaufort, 

 being examples) ; the other where students of 



