October 1, 1896.] 



KNOWLEDGE 



227 



times the diameter of the sun. Near the western edge there 

 were two large prominences, whilst only a few smaller cues 

 were to be seen on the eastern edge. Two or three seconds 

 before totality ended, a narrow, dark streak of strong red 

 light made its appearance on the western edge of the 

 moon, and next moment the sun burst forth in a blaze of 







glory, and tie corona vanibhid ; but that impressive Fcen^, 

 occupying one minute and thirty-five seconds, is one that 

 can never be forgotten. During totality, the planets 

 Mercury, Venus, and Jupiter were plainly to be seen, and 

 some of the well-known constellations. I could not spare 

 the time to get a glimpse of Regulus, but it was seen by 

 Captain Boggs and the chief otMcer of the ship, and also 

 by some of the passengers. We closely observed the 

 eclipse till the final contact, and within half an hour of 

 totality clouds drifted across the sun resembling the 

 cloud-belts seen upon the planet Jupiter. Just before the 

 last contact the clouds were still drifting in that direction, 

 so that we had to watch most carefully to detect the exact 

 moment of the final contact. 



The following are the data of the eclipse, furnished by 

 Captain Boggs and E. Roberts, chief otficer, and made 

 according to the ship's chronometer and Greenwich mean 

 lime : — 



Augiut 



First contact. 

 Total ob-ciir.ition began, 

 total obscuration ended. 

 Last contact. 



Mary Proctor. 

 (Daughter of Bicliard A. Proctor.) 



CLAVIUS AND HIS NEIGHBOURS. 



By E. Wai.tkr Maunder, F.R.A.S. 



TTTE accompanying plate, which exhibits about tho 

 one-thirtieth part of the moon's apparent disc on 

 the magnificent scale of forty-four inches to the 

 lunar diameter, is reproduced from a fine photo- 

 graph taken with the great refractor of the Lick 

 Observatory, and which Prof. ]■',. S. lloldeu. the director 

 of the Observatory, has most kindly placed at our dis- 

 posal. It represents sunset on perhaps the most broken 

 and mountainous region of the entire moon, /.<•., that 

 which has the great walled plain of Curtius as its centre. 

 In the illuminated portion of the plate we find the triant- 



walled plain of Clavius, one of the princes of lunar for- 

 mations, in a region of great walled plains only less 

 striking than itself, some of them, though not equal to it in 

 area, exceeding it in depth. 



The region is one which undergoes the most striking change 

 of appearance as the moon's age increases from the eighth 

 to the twenty-third day of the lunation. For these broad 

 and deep plains, so bold and striking, and with contrasts 

 of light and blackness so intense under the rising or the 

 setting sim, vanish almost completely when the sun shinea 

 down upon them from their meridian. Some indication 

 of this contrast may be gained from the photograph itself, 

 though it is less pronounced on the sensitive plate than to 

 the eye, and the field here shown to us does not embrace 

 in the main a greater arc than is traversed by the moon'a 

 terminator in three days. But even so, the difference is 

 very great between the distinctness of such formations as 

 Bettinus, Longomontanus, and Wilhelm I., on the east 

 (right-hand) side of the plate, and C'urtius, Moretus, and 

 Zachon the west (left-hand). The disappearance of these 

 great walled plains is so complete under a hii^'h sun 

 that Miidler's words have passed into a proverb : " The full 

 moon knows no Maginus." At such times the feature 

 of the district is not the massive ramparts of the 

 broad plains, nor the rugged and intricate 

 mountain lands interlaced between them, but the 

 long bright streaks radiating from Tycho— which 

 J lies just outside the present plate to the north 

 — and extending to the very limb. 

 With such an infinite complexity of detail, and with such 

 entire and rapid change of presentment, the region of our 

 plate offers a fine field for the selenographical student. 

 The careful and thorough scrutiny of each of the numerous 

 formations here presented to us under all the variations 

 of libration and illumination, would demand the fullest 

 efforts of a large corps of observers. Under such circum- 



Kcy lo I'lato. Clavius and his Neighbours. 



stances it would bo idle to attempt here anything like a 

 full description of the entire district. A brief mention of 

 the principal objects will suffice. 



Clavius, by far the largest member of the group, has an 

 area about e(|ual to that of the six northern counties of 

 England, and its wall, for the most part, considerably 



