Greenwich may still need a correction, we have reckoned the longitude 
and also the latitude on the map from Jidda, Mecca-gate. 
At the conclusion of this paper, which has proved that much 
advice and help has come to me from many sides, the only thing 
left for me to do, is to express my sincere gratefulness to all those from 
whom I have received this help. 
Postcript. 
(November 1912). 
In order to investigate the accuracy of our time-determinations 
we had compared the results from the eastern and the western star, 
but in doing this no attention liad been paid to the fact, that in most 
cases the times of observation of the two stars lie too far apart to 
neglect the rate of the chronometer in the interval. 
Therefore this comparison has been made anew after correcting 
the differences E—-W; the results, however, have not been materially 
changed. We now obtained 
Jidda 23 nights HK—W = + 03.12 
Mecca13 … + 0.25 
Together E—W —= + 05.16 = 05.10 
against before + 0-11 + 0-10. The constant error in the zenith- 
distances would be found now Az==J1".2 against before + 0.8, 
but just as before it is small. 
As mean error of the difference from one night we now found 
+ 0558 and therefore as mean error of a time-determination trom 
two stars + 05.29 against before + 05.32. The accordance of the two 
stars was somewhat improved. 
Chemistry. — “On a new modification of sulphur’. By Dr. 
A. H. W. Aten. (Communicated by Prof. Horr.EMAN). 
Communicated in the Meeting of September 28, 1912. 
This investigation originated in an observation by ARONsTeIN and 
MEIHvIZEN *), who noticed that when a solution of sulphur in sulphur 
chloride (S,Cl,), supersaturated at the temperature of the room, is 
heated to 170°, no sulphur erystallises on cooling. [ have afterwards 
repeated this experiment and demonstrated that the solution of S in 
SCI, which has been heated to 170° not only fails to deposit sulphur 
at the temperature of the room, but is even capable of dissolving a 
1) Verhandelingen Kon. Akad. Wel. Amsterdam, 1898. 1. 
