Observers' Field Reports 71 



10 daj's, according to the Arab owners of these animals. In an emergency one could count 

 on the camel doing 15 days without water. But this statement needs to be applied with 

 care by the prospective tra^'elcr, for let him be overtaken by the hot season and encounter 

 temperatures of 50 C, and he will find that these animals will suffer after 36 hours. Incau- 

 tious procedure will bring jiiinishment under these conditions. As regards food require- 

 ments, the camel will not last long without any food; but he seems to have the power of 

 storing a lot of reserve energy in the hump, which is the criterion of the condition of the 

 animal. If the hump is large and fine, the animal is in good condition. When an animal 

 with a good luniip is taken, he may be used for a month or two over areas where pasturage 

 is insufficient. Once the reserve of the hump has been expended, he gives way and is use- 

 less. He must either be abandoned or be put into a good pasturage for several months 

 until he can recuperate and build up a hump again. Unless the route is missed, water is 

 ordinaril)' not a serious problem in Saharan travel. Pasturage, however, is always a serious 

 question. 



South of Ouargla and as far as Fort Motylinski, observations, as many as feasible, 

 were made practicallj' every day, the work being alternated between Observer Sawyer and 

 mj'self, one man taking charge of camp work, the other observing. At the expiration of 

 every 3 days of travel, complete observations were made, generally without halting the 

 progress of the party. The afternoon was devoted to observing as usual, but on the follow- 

 ing morning 2 soldiers were retained as protection while the station was completed, and 

 the main body of the caravan sent on at the usual time. After completion of the observa- 

 tions, the camp of the main party was rejoined by a forced march, which several times 

 lasted well into the night. 



Instead of following the direct route to In-Salah, the party was directed westward 

 to El-Golea, in order that a last time-comparison with the observatory at Bouzareah might 

 be obtained by telegraph. On November 22 Hassi Hadjar was reached, 2 stations having 

 been established en ro^ite. Here occurred a curious incident. Three of the camels were 

 reported blind by the drivers. A desert herb grows in this vicinity, the pollen or some 

 other emanation from which gets into the eyes of the camel and blinds them, incurablj', 

 so the .\rab affinned. After repeated injections of mild carbolic acid solutions these ani- 

 mals recovered their sight. The soil here is apparently very alkaline, so much so that 

 some of the wells have undrinkable water. 



After Hassi Hadjar, a severe stretch of desert was encountered in which 6 days were 

 spent without encountering water, but abundant pasturage was always found. In this 

 interval the surface of the desert frequently presented itself as a surface of smooth, thinly- 

 sand-strewn rock, so that several stations were established on sand dunes. Another curious 

 physical feature was observed on the surface of this rock-plateau. At numerous intervals 

 one encounters collections of rock broken to the size of railroad-ballast, rarely in heaps, 

 but most frequently in circular groups, well scattered, as though some large rock had struck 

 the surface of the plateau, exploded, and scattered these angular fragments. 



El-Golea was reached on November 30. Here two more camels were bought and obser- 

 vations were secured. Departure was made on December 3. As before, the desert to the 

 south of El-Golea was abruptly severer. On the 7th and 8th we passed over an especially 

 barren tract of bone-strewn desert to the north of the deserted post, Fort Miribel, camping 

 late on the afternoon of the 7th in absolute desert with no vegetation in sight, to obtain a 

 few magnetic declinations while the cook tried a tireless kitchen. 



Following the program of observations and travel already indicated, without mishap, 

 after passing through several beautiful small oases in its neighborhood, In-Salah was 

 reached on the afternoon of December 24. On the next day, in the afternoon, General 

 Bailloud's trans-Saharan expedition arrived. General Bailloud had been in command of 

 the 19th Army Corps of France and had already shown marked kindness and courtesy to 



