NATURE 
[May 29, 1902 
104 
THE FARMERS VEARS. 
Wk 
CARNAC AND ITS ENVIRONS. 
2 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 in 
one respect there is a vast difference. Instead of a few, 
arranged in circles, as at Stonehenge, we have an enor- 
mous multitude of the so-called menhirs arranged in 
many parallel lines for great distances. 
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 
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 Poly 
mathic Society of Morbiban at Plouharnel.! 
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 obliguity 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 is difficult to gather from his memoir and 
the small plans which accompany it, which 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, a Vorigine les alignments 
étaient orientés, comme le pense M. Gaillard, ils ne le 
pourraient plus étre aujourdhui ; au contraire, s’ils le sont 
actuellement, on peut affirmer qu’ils ne l’élaient 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 orienta- 
tions dealing with the farmers’ years, that is with ampli- 
tudes of about 24° N. and S. of the E. and W. points ; 
but in 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. 
I append a reproduction of one of M. Gaillard’s plans, 
which will give an idea of his use of the index menhir. 
It shows the cromlech and alignments at Le Ménec. 
The line A—Soleil runs across the stone alignments and 
is fixed from A by the menhir B, but there does not 
seem any good reason for selecting B except that it 
appears to fall in the line of the solstitial azimuth accord- 
ing to M. Gaillard. But if we take this azimuth as N. 
54° E., then we find the alignments to have an azimuth 
roughly of N. 66° E., which gives us the amplitude of 
24° N. marking the place of sunrise at the beginning 
of the May and August years, and the alignments may 
have dealt principally with those times of the year. 
I esteem it a most fortunate thing that while I have 
1‘ L’Astronomie Prehistorique.” 
laires, mensuelle 
administration des ‘ 
Published in ‘‘ Les Sciences Popn 
internationales,” and issued separately by tre 
Sciences populaires,” 15 Rue Lebrun, Paris 
NO. 1700, VOL 66] 
reyue 
been casting about as to the best way of getting more 
accurate data, Lieutenant Devoir, of the French Navy, 
and therefore fully equipped with all the astronomical 
knowledge necessary, who resides at Brest and has been 
studying the prehistoric monuments in his neighbour- 
hood for many years, has been good enough to write 
me a long letter giving me the results of his work in 
that region, in which the problems seem to be simpler 
than further south ; for while in the vicinity of Carnac 
the menhirs were erected in groups numbering five or 
six thousand, near Brest they are much more restricted 
in number. 
Lieut. Devoir, by his many well-planned and completajy 
accurate observations, has put the solstitial orientation 
beyond question, and, further, has made a most im- 
portant observation which establishes that the May and 
Echelle 
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Be ws opecg 
EF Morrev 5c 
Fic. 1.—Alignments at Le Méenec. 
August sunrises were also provided for by a system of 
alignments. He permits me to make the following 
extracts from his letter :— 
“Tt is about twelve years ago that I remarked in the 
west part of the Department of Morbihan (near Lorient) 
the parallelism of the lines marked out by monuments 
of all sorts, and frequently oriented to the N.E., or rather 
between N. 50° E. and N. 55° E. I had ascertained, 
moreover, the existence of lines perpendicular to the 
first named, the right angle being very well measured. 
“The plans, which refer to the cantons of Ploudal- 
mézeau and of St. Renan (district of Brest) and of 
Crozon (district of Chateaulin), have been made on a 
plane-table ; the orientations are exact to one or two 
degrees. 
7 
