1882. 1435 Texans: IN. Vi IAGssScZ. 
~ Looking at the above table, and rejecting the results from the appa- 
ratus of both BERNSTEIN and ABEL, which are faulty in construction, 
the following conclusions may be drawn: 
1. Open testers are not to be recommended, since the light vapors 
are lost. 
2. Closed testers should be so constructed as to prevent the loss of 
vapors, and to give conditions that obtain in burning an ordinary kero- 
sene lamp. This last fact is important in connection with the quantity 
of oil used. A glance at the table reveals the fact, that the greater the 
quantity of oil in the apparatus, the lower the “ flashing-point.” It 
is ridiculous to make a test on two ounces of oil, which is used in a 
lamp holding twelve or more ounces. The test should be made upon 
at least ten ounces of oil, and in an apparatus where the personal equa- 
tion of the operator shall have little or no influence. 
The paper of Mr. ELtiorr was discussed at some length by 
Prof. SEELEY, Dr. NEWBERRY and Mr. WotcorTt. 
March 20, 1882. 
LECTURE EVENING. 
The President, Dr. J. S. NEWBERRY, in the Chair. 
The larger hall was entirely filled. 
Ordinary business of detail was omitted ; and the regular lecture 
of the monthly course was delivered by Prof. JoHN K. REEs, on» 
the subject of— 
SOME RESULTS OF PHOTOGRAPHY AS APPLIED TO ASTRONOMY, 
(Abstract.) 
We find Mr, NORMAN LOCKYER, of England, stating in his book on 
““Star-gazing,”’ that ‘celestial photography was founded in the year 
1850 by Prof. BOND of Cambridge, Mass., who obtained daguerreotypes 
of the moon at about that date.” This appears to be anerror. Dr. 
HENRY DRAPER, of this city, in a paper published by the Smithsonian 
Institution, tells us that the first photographic representations of the 
moon ever made, were taken by his father, the late Prof. JOHN W. 
DRAPER. Prof. DRAPER presented his specimens to the New York 
Lyceum of Natural History. In the minutes of that body we find the 
following memorandum :— 
MARCH 23, 1840.—Dr. DRAPER announced that he had succeeded in 
getting a representation of the moon’s surface by the daguerreotype. 
The time occupied was ¢wemty mznutes, and the size ot the figure 
