~732 - reign of Ethelbert II (king of Kent)
The 'acre' is in common use.
~960 - reign of Edgar the peaceful
It was decreed that all measures must agree with standards kept in London and Winchester
1215 - reign of King John (lackland)
An agreement to have a national standard of weights and measures was incorporated into the magna carta.
1266 - reign of Henry III
An act of this date established that a penny (money) should weigh the same as 32 grains of wheat, twenty pennies to make one ounce, and twelve ounces to the pound. Eight pounds was to be the weight of a gallon of wine. You will notice the link between money and weight, and that 240 pennies equals one pound.
1304 - reign of Edward I
This is where things got complicated. A statute declared that for medicines a pound would be of 20 shillings, or 12 ounces. All other things would be weighed with a pound containing 15 ounces - in all cases an ounce being 20 pennies.
1352 - reign of Edward III
A statute of this year established the stone as 14lb - a value it has kept ever since.
1532 - reign of Henry VIII
An act of this year laid down that butchers should sell meat by haver du pois weight - from where we get avoirdupois.
1707 - reign of Queen Anne
The wine gallon, which was fixed at 231 cubic inches. This is the basis of the liquid measures still in use in the US of A. It must be said that this gallon is actually of Edward the first's time, the 1707 act really only clarifying its size.
1824 - reign of George IV
The famous 'weights and measures act (5 Geo IV c 74) established the 'Imperial' system of weights and measures. The act comes in to force in 1826.
1878 - reign of Queen Victoria
The troy pound was declared illegal. For avoirdupois weights, commercial weights could only be the following: 56lb, 28lb, 14lb, 7lb, 4lb, 2lb, 1lb, 8oz, 4oz, 2oz, 1oz, 1/2oz, 1/4oz, 2dr, 1dr. Until this date, it was common to see other denominations in trade use, especially 8lb.
1969 - reign of Elizabeth II
The apothecaries system was outlawed for dispensing medicines, in favour of the metric system.
1971 - reign of Elizabeth II
The 'L.s.d.' system of money was replaced with the 'decimal' system.
1972 - reign of Elizabeth II
The passing of the European Communities act hands over 'competance' for weights and measures legislation (and everything else come to think of it) to Brussels.