320 REMARKS ON TRAVELS 
three miles only, but the construction of the itinerary 
proves that this computation was more than one tenth too 
small. The result is twenty one English miles,* which is 
very near eighteen geographical miles and four tenths ; all, 
by my estimation, medium days, (or days of a medium 
caravan). Indeed, the small caravan to which M. Caillie 
then belonged may be balanced against these considera- 
tions — first, that though small in number it included a 
woman ; secondly, that all were on foot ; thirdly, that all 
were loaded. In traversing the desert, the day's journeys 
were of twelve hours and sometimes more ;t but exhaus- 
tion, thirst, and fatigue, prevented both the travellers and 
camels from keeping up the same pace as on their first 
departure, and a mile and a half an hour is a large al- 
lowance for the march. 
I ought here to report the opinion of M. Walckenaer, 
who has discussed with much sagacity this important 
geographical question :| he fixes at fifteen minutes the 
amount of a day's journey of a caravan heavily loaded ; 
this amount falls short by only one sixth of that which 
I have adopted, from our own experience in Egypt, 
and which further confirms the opinion of Major Rennell. 
* It is the same with the route from Timbuctoo to Arbate. 
t Impatience to arrive, and above all, the imperious necessity of 
reaching the wells, sufficiently account for these long journeys through 
the desert. 
X Recherches sur VAfrique septentrionale, &c., page 266. 
