By no means the least of the obstacles which hinder a quantitative analysis of Irish agriculture prior to 1847 is the chaotic state of weights and measures. Successive statutes had been introduced in an effort to secure uniformity, but had little effect even in official quarters. Thus, although 5 Geo. IV c. 74 set up, as from 5 January 1826, the ‘imperial standard’ as the only standard measure of distance, area, volume and capacity, the Irish Post Office continued to use the Irish mile in its cancellations at least up to 1856, and used the same unit in its published list of distances. Variations in the stone, hundredweight and ton, together with non-standard grain measures, were declared illegal in Ireland as from I July 1835, but practice again lagged far behind the law.
In the absence of any comprehensive survey of the actual state of weights and measures in Ireland in the first half of the nineteenth century, historians dealing with the period have tended to bypass the problem at the expense of ambiguity and inaccuracy.