iver Temperature. 301 
11 and noon. Renou suggested to M. Valin, in the 
instance of the Loire at Tours, to take his observations at 
11. Judging from the tables, which Dr Borius gives for 
the Senegal, noon was the hour best fitted in August for the 
purpose. For the temperate zone, the subjoined table, which 
I have constructed from Renou’s Loir tables, will be useful, 
with the necessary adaptations, for most rivers. It is 
certainly of importance to learn from its columns that if we 
employ the same hour of observation for obtaining the mean 
temperature in winter and in summer, we should be in error, 
since the hour of the mean in midwinter is the hour of three- 
quarters range in the middle of summer. The table ought 
to be serviceable in reducing to the same value the numerous 
observations on English and Scottish rivers which are con- 
tained in Dr Mill’s British Association Report, observa- 
tions which, through their having been made at very different 
hours, are in themselves somewhat difficult of comparison. 
This difficulty, however, has been made more apparent than 
real by the tables of Renou, and it is to be hoped that Dr Mill, 
who has here done for our own rivers what Forster has done 
for those of Central Europe, will initiate the inquiry again. 
Table of the Progress of the Temperature of the Low at 
Vendéme during the day, constructed from the tables of 
M. Renow (“ Annuaire Météorologique de la France,” 
1852). 
Lowest Onet Half Range, Three- Highest 
Tempera. | Oftange- | or Mean | ‘urbe | Teper 
January, 9am, [11.15a.M./12.15pP.M.] 1.30p.M.] 3 P.M. 
February, meee 10.30 ,, |11.404a.m.|12.30 ,, eer 
March, . haga Wie. firau js |im4s ., | ee ss 
April, (ed As 1d SONS ned Ae 53 
May, ores WhO cn OSes NOME eu | aA ee 
June, ame 9 WOO 5, PESTO CEN OP a 
July, (AGEY 97304535. <j yay le 200035 Sig tds 
August, lies OFABE ee le 2s ge icra, AS ss 
September, poe ts, its fs 3a; 
October, tah ee i we a css 
November, Sia 10 ame (tha! 3 Noon. 2; 
December, OE 11 45+ SL QoL DEP, Mee 1 P.M. Ber 
i 
