Scientific Intelligence. — Meteorologp, 423 



but it will be highly useful to complete, by accurate thermorae- 

 trical and hygrometrical observations, the vague accounts with 

 which we are now obliged to be satisfied. Burckhardt men- 

 tions that, during an invasion of the seimoum, he saw the ther- 

 mometer at Esnc in the shade rise to 131° Fahr., a temperature 

 which would perfectly justify all the assertions of Bruce, if the 

 British traveller had not added, that the air never continued in 

 that state longer than a quarter of an hour. 



In conclusion, is it true, as Burckhardt assures us, that the 

 hues of the atmosphere where the seimoum prevails, the colours 

 of the sun, whether red, yellow, bluish or violet, as mentioned 

 by so many other travellers, depend on the nature and colour of 

 the ground, whence the wind has raised the sand which it trans- 

 ports along with it ? — Arago. 



5. Fall of Ram from a serene STcy. — M. Wartmann has in- 

 formed M. Arago, that, on the 31st day of May last, at two mi- 

 nutes after seven o^clock in the evening, there was a shower at 

 Geneva, which lasted six minutes, the sky being perfectly clear 

 at the zenith, and no cloud being visible in the neighbourhood 

 of the place. This rain, whose temperature was lukewarm, fell 

 vertically in drops, at first sufficiently large and numerous, and 

 gradually became smaller and smaller till it ceased. The ther- 

 mometer at the time indicated a temperature of Q^°.5 Fahr. The 

 day had been one of frequent showers and sunshine. 



6. Uncommon Atmospherical Refraction at Dover. — When the 

 dense fog which overspread the horizon here on Friday se'ennight 

 had cleared away, about ten o'clock, the sky became so bright 

 that one of the most imposing views of the opposite coasts pre- 

 sented itself that ever was witnessed from our shores. It was dead 

 low water, which favoured the view, and it seemed as if a curtain 

 had suddenly been witlidrawn, exhibiting the whole line of the 

 French coast as distinctly as if it had only been a few miles off. 

 Calais was so plainly distinguishable that comparatively minute 

 objects were plainly discernible. Boulogne piers were perfectly 

 visible ; the sails of the vessels in that harbour were observed out- 

 spread, and the whole of the villages along the coast seemed so 

 close at hand that the spectator on Dover pier might fancy 

 them as near as the martello towers immediately adjacent to 

 Folkstone. — September 1838, Dover Chronicle, 



