The medieval and non-metric Imperial data is that 7000 grains make a Pound weight avoirdupois; 5760 grains for Troy & Apothecaries. Inconveniently, the only scientific data I can find of a fair age is 1824 Encyclopedia Britannica which has each ACTUAL grain being more like 65% of the STATED grain. The same source measures Length and finds each grain close to 0.345 inch rather than the '3 to an inch' usually specified. Has anyone got physical measurement data which eliminates this confusion?
1$\begingroup$ One suspects that agriculture selected for larger grains over time, and medieval to 1824 is a long time $\endgroup$– Jon CusterJun 8, 2022 at 15:39
$\begingroup$ Nice idea BUT ... the 1824 figure is SMALLER than that specified in Medieval times. That's why I need help. $\endgroup$– J KingJun 9, 2022 at 16:04
$\begingroup$ Then clarify the wording in the question which is ambiguous. Which grains are 0.345 rather than 0.333? $\endgroup$– Jon CusterJun 9, 2022 at 16:08
$\begingroup$ The LENGTH is 0.345 against a legal-fiction of 0.333 ie 3 to the inch. The discrepancy of 0.012 being maybe 3% This is close enough for my initial concerns. the WEIGHT is my concern where the actual of 1824 is some 30% LESS than it should be. I hope this is more clear. $\endgroup$– J KingJun 10, 2022 at 17:08
$\begingroup$ The Encyclopedia of 1824 notes the WEIGHT of a grain as 0.6688 of a legislated-grain. $\endgroup$– J KingJun 11, 2022 at 8:00
From which part of the head where the barley corns taken and how were they dried prior to measurement.
Charles Butler, a mathematics teacher at Cheam School, recorded the old legal definition of the inch to be "three grains of sound ripe barley being taken out the middle of the ear, well dried, and laid end to end in a row", and placed the barleycorn, not the inch, as the base unit of the English Long Measure system, from which all other units were derived
emphasis is mine.
John Bouvier similarly recorded in his 1843 law dictionary that the barleycorn was the fundamental measure. Butler observed, however, that "[a]s the length of the barley-corn cannot be fixed, so the inch according to this method will be uncertain"
The other thing to consider is did farming practices improve the barley crop over the years. Were barley corns larger in the 1800s than they were in the 1300s?