But although these subjects are apparently distinct, I think my readers will agree that the study of each has led to an identical result, namely, that in early times it was a question of the May year, and that the solstitial year was introduced afterwards. This was the chief revelation of the monuments when they were studied from the astronomical point of view. Without confirmation from some other sources this result might have been considered as doubtful, and the orientation theory might have been thought valueless. It has, however, been seen that folklore and tradition confirm it up to the hilt. I think it may be said, therefore, that the theory I put forward in this book touching the astronomical use of our ancient temples is so far justified. The British monuments I had considered before this appeal to tradition was made were the circles at Stonehenge, Stenness, The Hurlers and Stanton Drew, and the avenues on Dartmoor. These were studied generally, the main special result being that to which I have referred; we not only found alignments to sunrise and sunset on the critical quarter-days of the May years, but we found alignments to the stars which should have been observed either at rising or setting to control the morning sacrifices. But this inquiry had left out of account several circles in south-west Cornwall, of which I had vaguely heard but never seen. When I had written the previous chapters showing how fully May-year practices are referred to in the folklore of that part of the country, I determined to visit the circles, dealing with them as test objects in regard to this special branch of orientation. I had not time to make a complete survey; this I must leave to others; but with the help so readily afforded me, which I shall acknowledge in its proper place, I thought it possible in a brief visit to see whether or not there were any May-year alignments. In the following chapters I will give an account of the observations made, but before doing so, in order to prove how solid the evidence afforded by the Cornish monuments is, I will state the details of the local astronomical conditions depending upon the latitude of the Land’s End region, N. 50°. In the chapter containing some astronomical hints to archæologists I referred (p. 122) to the solstice conditions for Stenness beyond John o’ Groat’s, because those conditions afforded a special case, the solstice being determined by the arrival of the sun at its highest or lowest declination, which happens on particular dates which recur each year. But with regard to the May year, during the first week of May the sun’s declination is changing by over a quarter of a degree daily, so that we must not expect to find the declination of 16° 20′ (see p. 22) rigidly adhered to.