ESTIMATION OF VALUE. 153 
the latter is more appositely used in regard to a 
single definite portion of a commodity, or atleast 
in the simpler cases of valuation; while the 
former may be appropriated to cases of greater 
complexity, where we compute the value of a 
mass or number of commodities. When I 
say a yard of cloth is worth twenty shillings, 
or a pound, I express the value of the cloth in 
relation to silver. When I say that 1000 yards 
of cloth, 500 quarters of corn, and 20 tons of 
iron, are worth 3000 guineas, I estimate the 
value of these articles in gold. If it is ne- 
cessary to establish a distinction between ex- 
pressing and estimating value, it may therefore 
be stated to be, that the latter involves the idea 
of computation, which is not necessarilyimplied 
in the former. The distinction, however, is 
not essential, and the indiscriminate use of the 
terms can scarcely lead to error. 
Mr. Ricardo frequently insists, that if by im- 
provements in the methods of production the 
whole produce of a country were doubled, 
while the labour employed remained the same, 
this doubled produce would be only of the same