OP ARTS AND SCIENCES. 23 



estimate of the time of the signal " Past," This decision was made 

 before correcting the result for error of chronometer, and before com- 

 paring it with any other observation. 



At the third and fourth contacts, the recorder counted the seconds 

 from the chronometer, and the observers recorded the times of their 

 observations. At the third contact, the seeing was good, and the fol- 

 lowing note was made : " No black drop seen. Purposely used faint 

 image." The clouds impeded any similar observation at the second 

 contact. The telescope was somewhat disturbed by wind during the 

 observations at egress, which prevented the observation of additional 

 phenomena. 



S. C. Chandler, Jr. 



The first contact was looked for at a part of the limb estimated to 

 be 3° to 5° to the right of the apparent vertex. The notch was sud- 

 denly noticed still nearer the apparent vertex at the time given as 

 that of contact. Nineteen seconds later the notch had increased, 

 confirming the first observation with regard to the place of ingress. 



The time given as that of second contact is that of geometrical 

 contact in the opinion of the observer. Seven seconds before the 

 recorded time the contact had not occurred. Four seconds after the 

 recorded time it was still uncertain whether the contact was past. 

 Nine seconds after the recorded time the contact was certainly past. 

 No "black drop" was seen. 



Thirty-five seconds before the recorded time of third contact a shade 

 appeared on the sun's limb, very much fainter than the disk of Venus. 

 This shade increased in darkness, but did not seem to confuse the de- 

 termination of the time of geometrical contact, which is that recorded 

 for this phase of the transit. The recorded time must be as early as 

 that of geometrical contact, which might possibly, however, have been 

 thought to occur ten seconds later than the recorded time. Twenty- 

 two seconds after the recorded time, contact was certainly past by sev- 

 eral seconds. 



The fourth contact was very satisfactorily observed. Eight seconds 

 before the recorded time the notch was still certainly visible ; at the 

 recorded time it was certainly gone. 



The telescope was one belonging to the observer, and lately placed 

 on the equatorial mounting in the West Dome. No shade-glasses 

 were used. The necessary reduction of the light was effected by pre- 

 viously smoking the front surface of the crown and the back surface of 

 the flint lens of the object-glass. This was done by Mr. John Clacey, 



