Contains contemporary copies of letters sent form Heath to the Secretary of the Admiralty between July 1867 and December 1870, copies of enclosures (mainly letters by other naval officers, list of sails, purchases, officers' allowances, etc) with alphabetical index. 675 pages. Last 4 letters in volume in different hand; possibly autograph signed copies of 4 letters by Heath.

Notable entries include those regarding the suppression of the East African slave trade, with Heath's reports on the capture of slave vessels, proposals for more effective measures, and a long account of a meeting with the Sultan in Zanzibar.