VOL. LXXXI.] PHILOSOPHICAL TRANSACTIONS. 41 



ing from thence, we have in the first table the numbers IQSJ-, 1944-, and 1874, 

 for the time between Hagla and Mesjid Ali, in the 3 journeys respectively : and 

 the same table affords also the following comparisons between different places on 

 the route : 



In one instance 80^, and 78-§- ; 



In a second 1 17-I-, 1 iQi, and 1 164- ; 



In a third 53f, 54^, and 51i^; 



And in a fourth 17 H, I74i, and 168. 



Again, between Aleppo and Annah on the Euphrates, the numbers in the 2d 

 table stand thus : 128, and 126s-. 



We need not produce any more examples to prove the equal rate of motion of 

 a camel that is in any degree loaded ; or rather of a number of camels together, 

 where the rate will be determined by the slow-going ones ; and whatever rate, 

 in actual distance, may be deduced from these examples, must be applied to 

 loaded camels travelling in a body together, and not to light camels, or those 

 chosen for speed, whose rate appears to be at least i greater. By a light camel 

 is meant one that has only a man, or a very small quantity of baggage, on it ; 

 whereas a camel's load is 500 to 60O pounds ; and camels so loaded, form what 

 is termed the heavy caravan. Light caravan, on the contrary, is applied to 

 camels under a moderate load, or perhaps little more than half loaded. And 

 with respect to camels, either moderately or fully loaded, he perceives no dif- 

 ference in their hourly rate of motion : the difference alone appears in the length 

 of their day's journey. A camel, it is said, will not permit himself to be over- 

 laden ; and this may be the reason why the load does not affect his rate of 

 motion. 



It appears, that the direct distance between Aleppo and Bussorah, is 621 

 geographic miles, or 720 British, nearly. And Mr. Carmichael's route, traced 

 by a compass, through all its principal bendings, and calculated trigonometrically, 

 gives 688 geographic miles, or of British 797- It follows then, of course, that 

 as the same gentleman was 322 hours on the road, the mean hourly rate of the 

 camel's motion, was 2.475 British miles. Colonel Capper's route, though easily 

 traced on the map, is not correct enough in its particulars, to serve as an au- 

 thority equal to Mr. Carmichael's ; and the like may be said of Mr. Hunter's : 

 but they must both be allowed to corroborate Mr. Carmichael's in a general 

 way 5 for as nearly as Colonel Capper's route can be traced, over the Chaldean 

 Desart, the hourly rate of his camels was 2.51 per hour; and that of Mr. 

 Hunter's 2.585. 



We come now to the Little Desart route. It has been noticed, that Mr. 

 Irwin employed 128 hours on his journey from Aleppo to Annah ; and 654- more 

 (allowing for his accelerated rate 3 hours,) between Annah and Bagdad ; altoge- 



VOL. XVII. G 



