The plants, ten or twelve feet high, grew so closely together that air was excluded, and so much sulphuretted hydrogen gas evolved that by one night's exposure the bottom of the boat was blackened.

Myriads of mosquitoes showed, as probably they always do, the presence of malaria.
We hastened from this sickly spot, trying to take the attentions of the mosquitoes as hints to seek more pleasant quarters on the healthy shores of Lake Nyassa; and when we sailed into it, on the 2nd September, we felt refreshed by the greater coolness of the air off this large body of water.

The depth was the first point of interest.

This is indicated by the colour of the water, which, on a belt along the shore, varying from a quarter to half a mile in breadth, is light green, and this is met by the deep blue or indigo tint of the Indian Ocean, which is the colour of the great body of Nyassa.

We found the Upper Shire from nine to fifteen feet in depth; but skirting the western side of the lake about a mile from the shore the water deepened from nine to fifteen fathoms; then, as we rounded the grand mountainous promontory, which we named Cape Maclear, after our excellent friend the Astronomer Royal at the Cape of Good Hope, we could get no bottom with our lead-line of thirty-five fathoms.