Idea agriculturæ. [electronic resource] : The principles of vegetation asserted and defended. Being an essay on the theory and practice of husbandry: Proceeding on the three noted mediums of improvement, viz. marle, lime, and shells, principally relating to the Isle of Anglesey. With rules and directions to find out the latter (wonderful in fertilizing the barrenest land) on other shores of Great-Britain and Ireland, where the like beds of broken shells, the winnowings of the sea, must naturally lye, if the like vast plenty of shellfish, do breed on the coasts, and in all probability, will be found, if they be fought for, according to these directions. By Henry Rowlands, vicar of Llanjdan, in the Isle of Anglesey; author of Mona antiqua: wrote in the year 1704.