16 NOTES BY THE EDITOR. 



such success, that even in the brief space of a year the vast blank on all 

 former maps has been materially reduced. Mr. Oswell, and the mission- 

 ary Livingston, his companion, to both of -whom we are indebted for our 

 acquaintance with the Ngami Lake, have pushed their researches north- 

 wards to 17 deg. 25 min. S. latitude, and between 24 deg. 30 min., and 

 26 deg. 50 min. E. longitude, and have traversed a considerable track, 

 watered by deep and constantly flowing streams, which they believe to be 

 feeders of the river Zambesi. We learn from them, that the Zonga, which 

 was to the east from Lake Ngami, is dissipated and absorbed in sands and 

 salt-pans, and the travellers passed over a large salt incrustation of about 

 100 miles in length and 15 miles in width, and saw many others lying 

 to the north of the spot where the Zonga loses itself. Considerably to 

 the north of these great natural salt pans, a population was met with, 

 more advanced in intelligence than most of the tribes of South Africa. 

 They also relate as a striking incident, that shortly before their arrival, 

 the slave-dealers had, for the first time, penetrated from the west coast, 

 and through the temptation of gaudy European goods had purchased 

 many children. 



Researches made in Africa by Mr. Galton, an English traveller, between 

 latitude, 17 deg. 58 min. S., and longitude, 21 deg. E., taken also in con- 

 nection with the explorations of Messrs. Oswell and Livingston, show, 

 that the central region of Southern Africa, instead of being mountainous, 

 is a watershed of no great elevation, and that the most central portion of 

 it is occupied by a succession of lakes, of which Ngami is the southern- 

 most. 



Under the direction of the Swedish Government, a topographical survey 

 extending over 8700 geographical miles is now in progress. Levellings 

 and trigonometrical surveys fromTorneo to Alten, in the North Sea, will, 

 when finished, give not only the relative heights of the Gulf of Bothnia, 

 and the North Ocean, but will also serve as fixed data from whence to 

 calculate the greater or less irregularity of the rise, or depression of the 

 Scandinavian lands. 



The most perfect topographical and geographical maps which perhaps 

 have ever been produced, are those of the cantons of Appenzel and St. 

 Gallenj in Switzerland, brought out during the past year, by M. Ziegler. 

 These maps, the part only of a large survey, are on a scale of 2 1-2 inch- 

 es to amile, or 1-25,000. The lights are all thrown in perpendicularly, and 

 the altitudes of each terrace, valley, or mountain-top is inserted in num- 

 bers on a most exquisitely finished lithographic relief. 



The great military map of France is also in active progress ; and 149 

 sheets out of 258 have been already published. As an illustration of the 

 gigantic nature of this work, it may be stated, that since this survey was 



