It has long been known that the stones which compose the prehistoric remains in Brittany are generally similar in size and shape to those at Stonehenge, but, as I have already stated, in one respect there is a vast difference. Instead of a few, arranged in circles as at Stonehenge, we have an enormous multitude of the so-called menhirs arranged in many parallel lines for great distances. Some of these are unhewn like the Friar’s Heel, some have as certainly been trimmed. The literature which has been devoted to them is very considerable, but the authors of it, for the most part, have taken little or no pains to master the few elementary astronomical principles which are necessary to regard the monuments from the point of view of orientation. It is consoling to know that this cannot be said of the last published contribution to our knowledge of this region, which we owe to Monsieur F. Gaillard, a member of the Paris Anthropological Society and of the Polymathic Society of Morbihan at Plouharnel.[18] M. Gaillard is a firm believer in the orientation theory, and accepts the view that a very considerable number of the alignments are solstitial. But although he gives the correct azimuths for the solstitial points and also figures showing the values of the obliquity of the ecliptic as far as 2200 B.C., his observations are not sufficiently precise to enable a final conclusion to be drawn, and his method of fixing the alignments and the selection of the index menhir are difficult to gather from his memoir and the small plans which accompany it, which, alas! deal with compass bearings only. All the same, those interested in such researches owe a debt of gratitude to M. Gaillard for his laborious efforts to increase our knowledge, and will sympathise with him at the manner in which his conclusions were treated by the Paris anthropologists. One of them, apparently thinking that the place of sun rising is affected by the precession of the equinoxes, used this convincing argument:--“Si, à l’origine les alignements étaient orientés, comme le pense M. Gaillard, ils ne le pourraient plus être aujourd’hui; au contraire, s’ils le sont actuellement, on peut affirmer qu’ils ne l’étaient pas alors!” M. Gaillard is not only convinced of the solstitial orientation of the avenues, but finds the same result in the case of the dolmens. I cannot find any reference in the text to any orientations dealing with the farmers’ years, that is with amplitudes of about 25° N. and S. of the E. and W. points; but in the diagrams on pp. 78 and 127 I find both avenue and dolmen alignments, which within the limits of accuracy apparently employed may perhaps with justice be referred to them; but observations of greater accuracy must be made, and details of the heights of the horizon at the various points given, before anything certain can be said about them.