In November 1587, Borough addressed a letter to the governors of the Muscovy Company upon their affairs in Russia; this document, probably on account of its great length, has not yet received the attention it deserves. Among other things, it seems to expose in the strongest possible way the devious policy of Sir Jerome Horsey and his harsh treatment of J. Peacock and other agents sent out by the company in 1585. In this letter is a discussion of the decay and improvement of the Russia trade.
