1818.] Observations on the River Zaire. 53 



b, door for stoking. 



c c, passages for heated air to consume the smoke. 



Fig. 2. Transverse section, in which the same letters refer tQ 

 the same parts as in Fig. 1. 



dd, entrances for air to inflame the smoke. 



e e, vertical passages behind the linings of the fire-place 

 through which the air ascends and becomes heated. 



Article VI. 



Observations on the River Zaire. Collected from the Journals 

 of Capt. Tuckey and Prof. Smith. 



Although the first view of the river Zaire convinced the 

 gentlemen who had undertaken to explore it, that its magnitude 

 had been very much exaggerated, still it was found to be a 

 considerable stream, perhaps the most so of any of the African 

 rivers which discharge themselves into the Atlantic. The depth 

 of the river at its mouth appears indeed to be very great, as a 

 common sounding line of ICjO fathoms did not reach the bottom ; 

 but its extreme breadth was scarcely three miles, and its velocity, 

 concerning which such wonderful accounts had been received, 

 was never more than five knots an hour, and often not more than 

 two and a half. It had been asserted that the river was always 

 in a state of full flood ; and on this fact had been principally 

 founded the hypotheses of its being the embouchure of the 

 Niger, or at least of its extending up into the heart of the conti- 

 nent beyond the equator ; this, however, was found to be erro- 

 neous, as during the short stay which the expedition made in the 

 country, they observed the swell of the water distinctly to com- 

 mence in the beginning of September ; and from all the inform- 

 ation which they could obtain, they were led to conclude that, 

 with respect to its periodical floodings, it did not materially 

 differ from the other tropical rivers. The report that its stream 

 was so powerful as entirely to resist the effect of the tide appeared 

 to be equally incorrect. Near the mouth of the river, its banks 

 are low, and formed of alluvial earth ; they are covered with 

 impenetrable thickets of a luxuriant vegetation of the mangrove, 

 and other plants of similar habits, and the stream is frequently 

 divided into several >channels by low swampy islands. The loose 

 texture of the banks of the river causes perpetual changes in the 

 line of the coast and the direction of the currents, and frequently 

 small fragments of the matted turf are detached and float down 

 the stream, with the cyperus and other gramineous plants still 

 remaining upon them. These, which appear to have been very 

 inconsiderable in size, were magnified by the Portuguese into 



