III.— EEPOHT ON METEOEOLOGICAL AND 

 ALTIMETKIC OBSERVATIONS MADE BY 

 H.R.H. THE DUKE OF THE ABRUZZI'S 

 EXPEDITION TO RUWENZORI (1906). 



By Prof. DOMENICO O.MODEI. 



The meteorological ol)servations were made during the whole journey, 

 from 16th May to 12th August, for the twofold purpose of first giving an idea 

 of the climate of these regions, at least for the short time of stay, a-nd then of 

 determining, at least approximately, the altitudes of the various places, and 

 especially of the more important points of the Kuwenzori Kange, which was the 

 chief o1)jective of the expedition. 



The instruments used in the observations consisted of three mercurial 

 barometers * of the Fortin type, one registering barometer, three aneroids, two 

 hypsometric thermometers, three thermometers and one psychrometer. 



Before starting, these instruments were carefully compared with the 

 normal instrimients, and to all the data, which are recorded farther on, were 

 applied the terms of correction thus established. 



During the first part of the journey from I']ntel)bet to Fort Portal, from 

 16th to 28th May, the observations for pressure, temperature and humidit}', 

 as well as those relating to the state of the weather, Avere taken cAery day at 

 noon, while other less complete observations were made at 15 and 21 o'clock. 

 The summary of the observations is contained in the accompanying Table I. 

 The maximum and minimum temperatures have reference to the whole period 

 of the stay of the expedition in a given station, that is, generally from about 

 10 oi' 11 in the morninii- till the fii'st antemeridian hours of the next dav. 



* Two graduated from 720 to 240 mm., and one from 480 to 290 mm. for the uplands. 



t Here there is an observatory, the altitude of wliieli is known, hence it was taken as 

 the basal station for the deter]nination of the altitudes of i)laces between Entebbe and Fort 

 Portal. 



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