The New Student's Reference Work/Nyasa

Nyas′a or Nyanja, the most southern of the great East African lakes, is 260 miles from Tanganyika and 400 miles from the east coast.  It is 1,570 feet above sea level, very deep, rapidly descending from its high and rocky shores, and measures about 350 miles long by 40 miles broad from east to west.  It was known by the Portuguese as Maravi in the 17th century, but was first navigated by Livingstone, and its situation exactly determined in 1859.