The book, "Arithmetic of Freemasonry" was written W. Bro. Rev. F. de P. Castells, A.K.C. who also wrote "The Apocalypse of Freemasonry". The Rev. Castells states that the ideas for his lectures were:

"...first suggested to my mind when engaged in preparing a lecture on the Hebrew Names for the Deity, which I gave to the Bible Study Guild, organised by myself at Bexley Heath, Kent. At that time I was not yet a member of the Royal Arch, but still I could see that the facts I had observed had a decided bearing on Masonry, and soon afterwards I developed them in a lecture on, "The Hebrew Words of the Masonic Ritual", which I delivered at the Lodge of Instruction carried on in connection with the North Kent Lodge, 2499. Later, having joined the Lullingstone Lodge, 1837, Wilmington, when invited to give a lecture there, I undertook to deal exclusively with the Numbers of the Ritual, but in Relation to the Hebrew Name of God." This lecture was subsequently given at the Mid-Kent Masters Lodge, 3173, Chatham, the Leeds Association of Installed Masters, and elsewhere, when I had fresh opportunities for testing the accuracy of my opinions before publishing them in book form..." pg 5-6

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