MR PARIES FIRST JOURNEY. 
331 
tities from the interior districts. The trade of the 
negroes is conducted by barter ; and, in order to 
adjust the value of their different articles of com- 
merce, they appeal to a nominal standard, which, 
from Senegal to Cape Mount, is termed a bar ; 
from Cape Mount to Cape Palmas, a piece ; from 
Cape Palmas to Whidah, an achey ; from Whidah 
to Benin, a pawn ; and from Benin to Gabon, a 
copper. These denominations originated from the 
particular species of merchandize for which the ne- 
groes shewed the greatest avidity, when Europeans 
began to trade on these coasts. On the Gambia, 
that quantity of any particular species of goods, 
which is valued at a bar of iron, is denominated a 
bar of that commodity. 
On 2d December 1795, at the commencement 
of the dry season, Mr Park departed from Pisania, 
without waiting for the coffle, a caravan of slatees, or 
slave-traders, of whose jealousy he was apprehen- 
sive. He advanced into the kingdom of Walli, at- 
tended by two negro servants, and accompanied 
by two slatees of the Serawoolli nation, and two 
free Mahometan negroes, of whom one was going 
to Bambara, and the other, a blacksmith, who had 
been employed by Dr Laidley, was returning to 
Kassan, his native country. One of his servants, 
named Johnson, who had been in England, and 
spoke the English and Mandingo languages, was 
hired at the rate of fifteen bars a month, five of 
