80 Land Magnetic Observations, 1911-13 



D. W. Berky, on Magnetic Work in French West Africa, Military Territory 

 OF Niger, Dahomey, and Nigeria, July to December 1913. 



On July 20, 1913, the trans-Saharan party was separated, and Observer H. E. Sawyer 

 was put in charge of the party that was to go to Dakar. On the evening of the same day, 

 accompanied by the interpreter and having an ass transport-caravan, I left Timbuktu in 

 order to make Cabaret that night for an early departure in the morning on the barge fur- 

 nished by Lieutenant-Colonel Sadorge. Two kilometers from Timbuktu a violent tor- 

 nado overtook us, with pitch darkness, lightning, thunder, and pouring rain. After much 

 trouble we camped in the middle of the road and spent the night in a very bedraggled condi- 

 tion. Early the next morning we arrived at Cabaret and found our crew was not yet 

 ready to depart. However, at noon the crew poled us out into midstream and the descent 

 of the Niger was commenced. Since the portion of the Niger between Gao and Timbuktu 

 had already been covered by observations on the way to Timbuktu, no observations were 

 made west of Gao. 



Gao was reached in the evening of July 30. On the following morning the departure 

 was delayed to 8 o'clock in order to permit time observations to be made. August 2 the 

 military post at Ansongo was reached, where magnetic observations were made. The 

 river journey was resumed at 3 p. m. the next day. On August 4 we encountered the first 

 of the numerous rapids between Ansongo and Labbezanga ; there were rapids and rocks 

 most of the day, as also the next. By the close of August 5, a half-dozen holes had been 

 punched into the bottom of the steel barge. On August 6, after passing through 3 rather 

 strong rapids, we arrived at the principal rapids of the series, the rapids of Labbezanga. 

 Here the river makes a drop of 6 or 7 feet in less than 100 yards. Having passed through 

 the rapids safely, the crew was presented with a piece of mutton to celebrate the successful 

 descent. 



Immediately south of the rapids, on the island of Labbezanga, a magnetic station was 

 established. South of the rapids the country for the first time begins to change its desert 

 character, and trees of a fair size begin to appear. On August 12 the military post of Tilla- 

 bery was reached and observations were made. The Niger in this region presents a curious 

 condition. It is split into numerous branches, many of them small. Thirty kilometers is 

 the reported width of the system of small channels into which the river is here divided. 

 Not infrequently either bank of the channel we were following could be touched by one of 

 the river poles of the crew. 



On August 17 we arrived at Niamey and the magnetic station established here by 

 Captain Tilho was reoccupied. During this stage of the descent, tornadoes accompanied by 

 rain were of frequent occurrence. Say was reached on August 20 and observations were 

 made after some delay on account of a tornado and rain. On August 23 we entered into an 

 uninhabited belt thickly infested with the tsetse fly. During the whole day, instead of 

 banks teeming with cattle and full of villages, only a few pigeons and some monkeys were 

 seen. The fly here encountered is inferred from printed cuts of the tsetse fly to have been 

 the Glossina fusca. Its bite had exterminated cattle and game, but was not fatal, so far 

 as known, to human beings. Towards the evening of the 25th the tsetse nuisance began to 

 abate, and that night we stopped at Bosia, the first native village on the south side of the 

 belt. Here magnetic observations were made. 



On August 29 we arrived at Gaya, the last French post on the Niger. Instead of con- 

 tinuing on the Niger to the coast, as originally intended, it was decided to leave the river 

 and to follow the route of the "Mission Tilho" through Dahomey, reaching the coast at 

 Cotonou. This change in plans was made because the river was considered impassable at 

 Boussa in Nigeria on account of the rapids. 



Negro carriers were engaged to carry the luggage, and hammock-bearers to carry the 

 interpreter and myself. As a full camp-equipment and some provisions had to be carried, 



