34 Proceedings of the Royal Physical Society. 
in the “ Description de l’Keypte.” Between 1826 and 1833 
Mr Robert Hay, an artist and an Egyptologist, possessed of a 
good fortune and abundant energy, made a large number of 
meteorological observations during his long sojourns on the 
Nile between Cairo and Abu Simbel. Those relating to the 
river were confined to the period between May 1830 and 
February 1832, and included two summers and one winter. 
In the first summer they were taken regularly at sunrise or 
at 6 A.M., and at sunset, about the best hours he could have 
selected for the purpose; and on this account alone they are 
valuable for determining the amount of the daily fluctuations. 
During the rest of the time they were taken at sunrise. The 
corresponding air observations, mostly made on the river, 
were recorded with astonishing perseverance five or six 
times a day, usually at sunrise or at 6 A.M., at noon, in the 
afternoon twice between 1 and 4 o’clock, at sunset, and late 
at night between 10 and 12. These observations are in his 
manuscript journal in the British Museum, and, with the 
exception of the entries on a few pages, they are all in 
pencil. Hay was at times the companion of Wilkinson, 
then engaged in his Egyptian researches; of Hoskins, the 
author of “Travels in Ethiopia”; of Linant de Bellefonds, 
the accomplished French engineer ; and of other travellers of 
repute. I have found no trace of the publication of this 
journal, and in the most recent Egyptian bibliography of 
Prince Ibrahim Hilmy, it is referred to as in manuscript. 
The accompanying diary is apparently full of interesting 
matter, though more destitute of adventure than the pub- 
lished narrative of Belzoni, who doubtless owed many of his 
experiences to his poverty. 
In April and December 1836 Russegger made a few 
observations at Terraneh and Cairo; but his most important 
inquiry was carried out in January 1836, when he took a 
series of temperatures between Cairo and Assouan, The 
results are given in his “ Reisen in Europa, Asien, and 
Afrika.” Somewhere about 1840 Captain Newbold made a 
series of over two hundred thermometric observations on the 
Nile water between Cairo and Thebes in June and July, 
They are very summarily discussed in a paper contributed 
