746 LIFE OF DA VID LIVINGSTONE, LL.D. 



to continue my survey of the lake, and to reach Usukuma, having been so 

 long absent from the Expedition, during which time many things contrary 

 to my success and peace of mind might have occurred. 



" I took my observations twice a day, with a sea horizon — one at noon for 

 latitude, and one in the afternoon for longitude — and I am sorry to say that if I 

 am right, Speke is about fourteen miles wrong in his latitude along the whole 

 coast of Uganda. The mouth of the Katongo River, for instance, according 

 to his map, is a little south of the Equator. I have made it by meridian alti- 

 tude, observed April 20, to be in N. latitude 0° 16' 0". Thus it is nearly with 

 all his latitudes. His longitudes and mine vary but little ; but this is easily ac- 

 counted for. The longitude of any position can be taken with a chronometer, 

 sextant, and artificial horizon, with the same accuracy on land as on sea. If 

 there is any difference it is very likely to exist in the error of the chronometers. 

 What instruments Speke possessed to obtain his latitudes I know not, but if 

 he found the altitude of the sun ascending above 65° he could never obtain it 

 with an ordinary sextant except by double altitude, and that method is not 

 so exact as taking a simple meridian on a quiet lake, with an ample horizon of 

 water. But there are various methods of determining one's latitude, and 

 Speke was familiar with many. My positions all round the lake have been 

 determined with a sea horizon. When near noon my plan was, if the lake 

 was rough, to seek the nearest island or a quiet cape at the extremity of a bay } 

 and there take my observations as deliberately as though my life depended 

 on their accuracy. But this task was, indeed, a work of pleasure for me, and 

 I have found a rich reward for most of my pains and stormy life on this lake 

 in looking at the fair extent of chart-work on the blank space of my map, 

 with all its bends, curves, inlets, creeks, bays, capes, debouchures of rivers, 

 now surely known by the name of Victoria Nyanza. Any errors which may 

 have crept into my calculations will be determined by competent authorities 

 on my return from Africa, or on the arrival of my papers in Europe. Mean- 

 time I send my map as I have made it. 



u The Katonga is not a large river, and has but one mouth. The Amionzi 

 River empties itself into the Nyanza, about eight miles W.S.W. of the Ka- 

 tonga. Ugunga stretches to the Kagerah, situated in S. lat. 0° 40'. On the 

 south side of the river begins Usongora, extending to S. lat. 1°. South of 

 1° is Kamiru, extending to S. lat. 1° 15'. Thence is Uwya, with a country 

 folk similar in enterprise to Ukerewe's people. Beyond Uwya is Uzinja, or 

 Uzinza, called by the Wanyamwezi, Mweri. Uzinja continues as far south as 

 Jordan's Nullah, and east of it is Usukuma again, while one day's sail from 

 Jordan's Nullah we pass Muanza, which Speke reached in 1858, and this 

 brings us home to Kagehyi, and to our camp, where we are greeted joyfully by 

 such as live, having, however, to mourn the poor fellows who, in our absence, 

 have been hurried by disease to untimely graves. I must be brief in what I 



