This is rather far-fetched since the foolscap watermark had already been in use for nearly two hundred years by that time.
The paper used for Parliamentary record-keeping was called foolscap in later years for the simple reason that was the paper size which had been chosen. It was not until into the eighteenth century that European paper makers began to standardize paper sizes and use specific watermarks to designate those sizes.
A dupe to rumours, and a tool of knaves; He’ll want no type his weakness to proclaim, While such a thing as fools-cap has a name. This modern usage of foolscap may also have contributed to the perception that foolscap is not good quality paper.
This poem was first published in the American Museum (Philadelphia, October 1787). Paper was very expensive into the mid-nineteeth century.
Therefore, most people were very careful to use only as much as they needed.
If, the next time you read a novel set in the Regency, one of the characters writes a letter on "foolscap," you will know they have a lot to say, since they have chosen a rather large sheet of paper.
Paper for printing could be sold by the ream, which was 480 sheets for most of the nineteenth century, or more often by the bale, which was ten reams.
Writing paper could be sold in flat sheets, by the ream.
About 1795, in England, the foolscap watermark was replaced by the figure of Britannia, even though the paper size continued to be referred to as foolscap.
The size of foolscap paper in the nineteenth century for both printing and writing was 16 1/2 inches by 13 1/4 inches.