e ordinary rate for double letters." Packets were
charged by the ounce, and the rate per ounce was four times that for a
single letter. As with the tariff of 1703, distances were calculated
according to the route actually followed by the couriers.

No further modification of the rates was made until after the
Revolution. The lease of the posts was due to expire on the 31st
December 1791, and it was decided that the Legislature should rectify
the tariff before the date at which the posts would revert to the
State.[189] A rectification was accordingly announced by the decrees of
the 17th-22nd August 1791. This revision slightly increased the rates of
1759. The initial rate of 4 sous for single letters circulating within
the same _d['e]partement_ was retained; the rate for letters circulating in
the same _arrondissement_ was fixed at 3 sous; between _d['e]partements_
the rate was increased, and varied from 5 to 15 sous, according to
distance of transmission; and the number of zones was increased to
eleven.[190]

Distances were no longer to be reckoned according to the length of the
route actually traversed, but from point to point as the crow flies. The
points were not, however, the actual points of posting and of delivery.
In each department a point was fixed upon, and the rate for all letters
posted or delivered in the _d['e]partement_ was calculated as from that
point; so that for a given weight the same rate was payable on all
letters exchanged between the same two _d['e]partements_. This system,
though comprising a very large number of rates, was much simpler than
the earlier systems. Any one town or village now had only 82 rates for
each step in the scale of rates, whereas under the previous system a
special rate must be calculated for every other town or village in
France. To assist the application of this tariff, a map showing the
central point fixed upon for each of the 82 _d['e]partements_, and the
distances from each central point to all others, was prepared and
supplied to every post office in France.

The tariff of 1791 also abolished the method of charge according to the
number of sheets, and substituted the simpler method of charge according
to weight alone. The maximum weight for a single letter was fixed at 1/4
ounce, and for heavier letters the rates were--

From 1/4 oz. to 1/2 oz. 1-1/2 times the rate for a single letter
" 1/2 " 3/4 " twice "
" 3/4 " 1