[1] The Seaman's Guide to the Navigation of the Indian Ocean and China Sea of 1867 said as follows:[1] Approaching Mayotta from the N.W., Zamburu cannot be mistaken; if approaching to the northward of the outlying shoal, keep Zamburu peak to the southward of S.E.

1⁄3 S., until Zamburu peak bears West, when run East from the latter until the next marks come on—viz., Point Congo on with the second summit of Pamanzi S.E. 3⁄4 S.

You may then pass close to Aombé islet, which is steep-to on its west and south sides, and thence pursue a midchannel course into Pamanzi bay, or round to the anchorage south-west of Zaudzi.

In rounding Zaudzi spit, do not haul to the southward until the four Nossi Effatsi islands open westward of Mognaméri.

The French frigates Cordelière and Somme sounded on this bank; it is a mile in extent N. by E. and S. by W., lying right in the fairway with least water 41⁄2 fathoms; at its north and south extremes there are 61⁄2 fathoms; it may be dangerous in parts for vessels of heavy draught.