298 



Mr. J. B. N. Hennessey. 

 Observatory Notes. 



[Nov. 20, 



1874. December. 



Chronometer 

 -Time. 



Greenwich Time. 



Remarks made bv Observer at the time. 



d. k. m. s. 



8 19 18 



20 



20 50 



22 33 



23 



22 

 32 



d. k. m. s. 



14 6 35 



35 



9 25 



11 8 



11 35 



24 



28 



13 



3 



25 



10 



13 



45 



26 



26 



15 



1 



28 



34 



17 



9 



29 



10 



17 



45 



16 

 17 



48 

 20 



36 

 36 



Ingress. 



Beautifully clear morning. ~No kaze. Eye- 

 piece 125. Two coloured glasses giving 

 a neutral or bluisk field. Missed tke 1st 

 external contact. 



Venus' edge on sun boils somewkat ; it is, 

 kowever, distinctly visible. 



Venus' outer edge, i.e., against sky, dis- 

 tinctly visible, because of a narrow edg- 

 ing, or ring of Hgkt, around some 30° of 

 tkat part of it furtkest from tke sun. 



Tke ligkt ring now extends around tke 

 wkole of tkat part of Yenus' edge against 

 tke sky, and is some 3" in width ; it is 

 brightest wkere furtkest from the sun. 



The ligkt ring against sky is well seen, and 

 looks undeniably like Venus' atmospkere ; 

 widtk some 4" ; definition excellent. 



Tke ligkt ring against tke sky ean be 

 plainly traced in continuation around 

 Venus on tke sun, wkere kowever it is 

 made visible ckiefly by tke movements 

 occurring in it of minute bright specks, 

 and also because it boils. Tke entire 

 ring is full of tkese minute brigkt specks, 

 which appear and disappear rapidly, 

 dancing about with little flashes. Defi- 

 nition excellent. 



Ligkt ring against sky wider. 



,, „ quite distinct. 



„ „ quite brigkt. 



Transit of Venus' dark edge across tke 

 sun's limb, i.e., 1st internal contact. 



Transit, by estimate, of outer edge of 

 Venus' ligkt ring (that was against sky) 

 across tke sun's limb. !N~o ligament or 

 pear-drop seen, though expected and care- 

 fully watched for. 



Brilkantly clear sky ; Hgkt breeze from south. 



Spectroscope set up, adjusted, and used. 

 Slit placed across Venus' centre gave a 

 black band all along tke lengtk of solar 

 spectrum. Slit placed tangential to 

 Venus' disk, gave a faint, narrow glim- 

 mer of light, slightly brigkter than solar 

 spectrum, instead of black band ; no dis- 

 placement of solar lines in grimmer. 



Egress. 



Eye-piece as before, 125. Of the two 

 colom-ed glasses used for Ingress, one 



