376 Professor H. E. Turner [June 5, 



were all found by Mrs. Fleming, who spends her life in examining 

 the vast collections of photographs taken under the enterprising 

 directorate of Professor Pickering. 



Of the remaining four, two fall to Dr. Anderson, who watches the 

 heavens assiduously from his quiet study window in Edinburgh. 

 The first, Nova Aurigae, had been shining for two months in the sky 

 without attracting attention, as was found by scrutiny of the Harvard 

 photographic records. If these could have been minutely examined 

 as they were taken, the star would have been found two months earlier. 

 But such immediate and comprehensive scrutiny is as impossible with 

 the limited staff of the observatory as it would be to have all the 

 books received at the British Museum read through as they came in. 

 With the second discovery. Nova Persei, Dr. Anderson was more 

 fortunate, catching the star within about twenty-four hours of its 

 blazing up ; and the news being flashed all over the world at once, 

 the history of the star was well recorded from the very outset. 



There remain two more of the ten discovered since 1882, the first 

 and the last. The first, Nova AndromedsB, appeared in the midst of 

 the great nebula in Andromeda, and its discovery was probably due 

 to the special attention naturally paid to that wonderful object. It 

 need not concern us further at present than to remark that there is a 

 close connection between new stars and nebulss, of which this is only 

 one illustration. 



The last of the ten, Nova Geminorum, was found at the University 

 Observatory at Oxford on March 24, and is the reason of my giving 

 this lecture. The discovery, although made in the course of regular 

 and laborious work on the stars, was not the outcome of any systematic 

 search. I will first briefly explain the work we are doing at the 

 University Observatory. In conjunction with seventeen other obser- 

 vatories scattered over the world, we are making a great map of the 

 whole sky. All the partners have instruments of similar pattern, and 

 each of them has undertaken to take about 1200 photographs, which 

 will cover twice over the portion of the sky assigned, and to measure 

 carefully the positions of all the stars on these plates. There are 

 about 400 stars on each plate, and each observatory must, therefore, 

 measure nearly half-a-million star images. This is a considerable 

 piece of work, and although at Oxford we have adopted the most 

 rapid and economical methods of getting through it, it has occupied 

 more than seven years. I am glad to say we are getting near the 

 end ; about sixty or seventy plates only remain to be measured, and 

 we hope to finish them before the end of the present year. 



In this hope we have been making special efforts since the be- 

 ginning of 1903 to get all the plates still required, so that none might 

 be left over till 1904. Taking advantage of a spell of fine weather in 

 February, Mr. Bellamy and I had secured about twenty or thirty 

 plates, but on proceeding to develop them we found they were wofully 

 deficient in faint stars. We had independent tests of developer and 

 sky, and were driven to conclude that the plates were inferior ; and 



