Near here we anchor for the night and are welcomed by a host of most noisy and vicious mosquitoes who have a particular partiality to good healthy European-fed blood. Again we are delayed to unload and this time into a small steamer the _Lagoon_--for the ship is still too deep in the water to cross the bar. This sandy obstruction has an unpleasant habit of shifting its position and it is necessary therefore to make careful soundings every voyage at this time of the year when the water is low. These are carried out by Captain Sparrow and Mr. Wright the chief Congo pilot with the aid of a most ingenious sounding machine. It consists of a simple pulley wheel raised on a standard about ten feet above the deck of a small pilot steamer. Over this passes a line weighted at both ends but unequally, and both weights hang down in the water, the heavier naturally being on the bottom of the river. To prevent this line--which corresponds to the ordinary lead line--trailing, as the boat moves forward, a second line is fixed to the weight and passes under water to the bows of the vessel where it is attached As the vessel passes slowly through the water, the weight rises and falls according to the level of the bottom, and the counterweight hauls in the slack of the line, which is marked in the usual way by coloured tapes. At any moment therefore, the depth of water can be determined by observing the tapes. There is now only 15-1/2 feet on the bar, so it is necessary to lighten the _Leopoldville_ still more before it will be possible to cross. Thus early one of the chief difficulties in the Congo the transport of goods--is demonstrated. A fine crocodile lies asleep on the bank within easy range as we go back to the ship in the launch, but no one has a rifle so his dreams are undisturbed. As the _Leopoldville_ will not be able to reach Boma until the morrow, we decide to go on in the _Heron_, a small ship which calls for all the State passengers. After Fetish Rock, the river bends sharply to the right and soon after Boma is in sight. At this distance however, the town merely appears as groups of white houses amid trees backed by green hills. Guarding the approach is a strong looking fort which already has a history, for it was captured by rebels and held for one or two days a few years ago.