396 PHENOMENA OF THE DESERT NIGHT. 



A few words upon the phenomena of the desert night 

 will bring this branch of our subject to a close. It is 

 the period of the twenty-four hours, when, according to 

 common consent among travellers in these regions, per- 

 fect enjoyment crowns the labours of the long and 

 sultry day with gladness, bringing with it a feeling of 

 ineffable repose and peace. The transition from the 

 fiery splendour of the day is of course a thing quickly 

 accomplished in these latitudes: twilight being confined 

 to a few brief moments only: and except during the 

 prevalence of hot winds, the advent of the night is 

 succeeded by a complete and immediate relief from 

 the exhausting heat of day and there are no mos- 

 quitoes or other insect pests to give trouble in the Desert 

 Zone, except perhaps in a few of the oases, the air 

 being too dry for these creatures. 



The rapid fall of the thermometer which follows 

 sunset, is a matter fully commented on in the section 

 on "Climates and Temperatures" as being a universal 

 and necessary consequence of the extreme dryness of 

 the desert air; where even dew is often found to be 

 completely or almost completely, absent; as evidenced 

 by the well-known fact, testified to by many travel- 

 lers, that firearms may, during the dry season, be left 

 upon the bare ground, night after night, without con- 

 tracting a particle of rust. * 



Throughout the sand plains, the dry sand which has 



* Thus in a letter of the Times Correpondent with the Soudan 

 Expedition of 1896 it is related that the caravan he was travelling with 

 discovered the skeleton of an Arab, supposed to have died of thirst in 

 the desert. Near the body was found a military rifle which was 

 afterwards identified as having been stolen some two years before from 

 one of the Soudanese Regiments. The wood work of it was much blanched 

 by weather, but the barrel and iron work were quite free 'from rust. 

 Seethe Times of June 2nd, 1896. 



