The saying casts no reproach on the Flemings. It always means, I believe that the sum to be received turns out less than had been expected. It is a commercial joke, and admits of explanation by reference to the early commercial transactions between the English and the Flemings.
I rely on the authority of The merchants mappe of commerce, by Lewes Roberts, London, 1638, folio, chap. 179:--
In Antwerp, which gave rule in trade to most other cities, the accounts were kept in livres, sols, and deniers; which they termed pounds, shillings, and pence of grosses. Now the livre was equal only to twelve shillings sterling, so that while the Antwerp merchant stated a balance of 1l. 13s. 4d., the London merchant would receive only 1l.--which he might fairly call A Flemish account!
The same instructive author furnishes me with a passage in illustration of a recent question on the three golden balls, which seem to require additional research. It occurs in chap. 181:--
"This citie [Bruges] hath an eminent market in place with a publicke house for the meeting of all marchants, at noone and evening: which house was called the Burse, of the houses of the extinct families Bursa, bearing three purses for their armes, ingraven upon their houses, from whence these meeting places to this day are called Burses in many countries, which in London wee know by the name of the Royall Exchange and of Britaines Burse."
BOLTON CORNEY.
I think it probably that the expression "Flemish Account" may have been derived from the fact that the Flemish ell measures only three quarters of our yard, while the English ell measures five quarters, and that thence the epithet Flemish was adopted as denoting something deficient.
Q.Q.
When commerce was young, the Flemings were the great merchants of Western Europe; but these worthies were notorious, when furnishing their accounts current, for always having the balance at the right side (for themselves), and hence arose the term. I am not at this moment able to say where this information is to be had, but have met it somewhere.
JUNIOR.