It sometimes happened also that a subject originally treated in a paper by Sir James Simpson required a volume to exhaust it. Thus, in the spring of 1864, he read to a meeting of the Society of Antiquaries of Scotland a "Notice of the Sculpturing of Cups and Concentric Rings on Stones and Rocks in various parts of Scotland;" but materials afterwards so grew on his hands that his original Notice came to be expanded into a volume of nearly 200 pages, with 36 illustrative plates. His treatment of this curious subject furnishes a model for such investigations.[5] Setting out with a description of the principal types of the sculptures, he investigates the chief deviations which occur. He next classifies the various monuments on which the sculptures have been observed, as standing-stones, cromlechs, stones in chambered tumuli, and stones in sepulchral cists. Another chapter describes their occurrence on stones connected with archaic habitations, as weems, fortified buildings, in and near ancient towns and camps, and on isolated rocks and stones. After a description of analogous sculptures in other countries, there is a concluding chapter of general inferences founded on the facts accumulated in the previous part of the volume. On the occasion of a rapid journey to Liverpool, Sir James Simpson visited a stone circle at Calder, near that city, and detected the true character of the sculptures on the stones, a very imperfect note of which I had recently brought under his notice. An account of this monument, which he prepared for the Historic Society of Lancashire and Cheshire, is printed in the Transactions of that body for 1865, and the following passages are quoted from it:--"Many suggestions, I may observe, have been offered in regard to the intent and import of such lapidary cup and ring cuttings as exist on the Calder Stones; but none of the theories proposed solve, as it seems to me, the hieroglyphic mystery in which these sculpturings are still involved. They are old enigmatical 'handwritings on the wall,' which no modern reader has yet deciphered. In our present state of knowledge with regard to them, let us be content with merely collecting and recording the facts in regard to their appearances, relations, localities, etc.; for all early theorising will, in all probability, end only in error. It is surely better frankly to own that we know not what these markings mean (and possibly may never know it), rather than wander off into that vague mystification and conjecture which in former days often brought discredit on the whole study of archaeology.