FEVER. 



101 



ness. Between Zanzibar and the Cape, five 

 brigs lost collectively 125 men from fever, dysen- 

 tery, and inflammation of the neck of the vesica ; 

 whilst others were compelled to start their casks, 

 and to touch at different 'aguadas 5 en route. 

 Hence skippers learned to fear and shun Zan- 

 zibar. During her 14 months' exploration of 

 the island and the coast the Ducouedic lost 16 

 men ; and to keep up a crew of 122 to 128, no 

 less than 226 hands were transferred to her 

 from the naval division of Bourbon and Mada- 

 gascar. Each visit to Unguja was followed by 

 an epidemic attack. Formerly as many as seven 

 whalers lay in harbour at one time; now (1857) 

 they prefer to water and refresh at Nossi-beh, 

 Mayotta, and especially at the Seychelles, a free 

 port, with a comparatively cool and healthy 

 climate, where supplies are cheap and plentiful. 



Besides the lagoon and the water nuisances 

 there is yet another. The drainage of the Zan- 

 zibar water-front is good, owing to the slope of 

 the site seaward. But at low tides, and after 

 dark, when the sulphuretted hydrogen is not 

 raised from the sands by solar heat, a veil of 

 noxious gas overhangs the shore, whose whole 

 length becomes exceedingly offensive. This is 

 caused by the shironi (latrinae) opening upon 



