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Now the date arrived at by Mr. Penrose and myself been brought by man, from distant localities. Prof. on astronomical grounds was about 1700 B.C. It is Judd inclines to the first opinion. not a little remarkable that independent astronomical The distinctions between these two kinds of stone and archæological inquiries conducted in the same are well shown by Prof. Gowland :vear should have come so nearly to the same conclu- “ The large monoliths of the outer circle, and the sion. If a general agreement bé arrived at regarding trilithons of the horse-shoe are all sarsens-sandit, we have a firm basis for the study of other similar stones, consisting of quartz-sand, either fine or coarse, ancient monuments in this country.
occasionally mixed with pebbles and angular bits of
flint, all more or less firmly cemented together with I have previously in these “ Notes " referred to the silica. They range in structure from a granular rock fact that the trilithons of the naos and of the outer resembling loaf sugar in internal appearance to one circle are all built up of so-called “sarsen stones.
of great compactness similar to quartzite. To describe their geological character, I cannot do
"The monoliths and trilithons all consist of the
examples of the compact better than quote, from Mr. Cunnington's "Geology granular rock. The of Stonehenge, "i their origin according to Prest. quartzite variety were, almost without exception, either wich :
hammerstones that had been used in shaping and
dressing the monoliths, or fragments which had been “ Among the Lower Tertiaries (the Eocene of Sir broken from off them. Charles Lyell), are certain sands and mottled clays, “ The small monoliths, the so-called 'blue stones,' named by Mr. Prestwich the Woolwich and Reading which form the inner circle and the inner horsebeds, from their being largely developed at these shoe, are, with the undermentioned exceptions, all of places, and from these he proves the sarsens to have diabase more or less porphyritic. Two are porphyrite been derived ; although they are seldom found in situ, | (formerly known as felstone or hornstone). Two are
argillaceous sandstone." DATUM LINE A B C D E F G H
" Mr. William Cun
nington, in his valuable 2
TURF AND MOULD Notes,' records the 3
discovery of two stumps 4
of 'blue stones' now
covered by the turf. 5
One of these lies in the 6
inner horseshoe between
Nos. 61 and 62, and 9 7
feet distant from the 8
latter. It is diabase.
The other is in the inner 9
CHALK ROCK circle between Nos. 32 10
and 33, 10 feet from the former, and consists of
a soft calcareous altered 12
tuff, afterwards desig13
nated for the sake of 14
brevity fissile rock.
The altar stone is of 15
micaceous sandstone." 16
SARSEN HAMMERSTONE I now come
second point, to which I 0 1 2 3 5
shall return in subse
quent “Notes." EEET
In studying the
material obtained from Fig. 6.-Face of rock against which a stone was made to rest.
the excavations, it was
found in almost every owing to the destruction of the stratum to which they that the number of chippings and fragbelonged.
ments of blue stone largely exceeded that of “ The abundance of these remains, especially in some the sarsens; more than this, diabase (blue stone) of the valleys of North Wilts, is very remarkable. Few and
were found together in the laver persons who have not seen them can form an adequate overlying the solid chalk (p. 15). Chippings idea of the extraordinary scene presented to the eye of of diabase
the most abundant, but there the spectator, who, standing on the brow of one of the were few large pieces of it. Sarsen, on the other hills near Clatford, sees stretching for miles before hand, occurred most abundantly in lumps (p. 20); him, countless numbers of these enormous stones, very few small chips of sarsen were found (p. 42). occupying the middle of the valley, and winding like Hence Prof. Gowland is of opinion that the sarsen a mighty stream towards the south."
blocks were roughly hewn where they were found These stones, then, may be regarded as closely (p. 40); the local tooling, executed with the small associated with the local geology.
quartzite hammers and mauls, would produce dust. The exact nature of the stones, called “blue Finally, I reach the third point of importance from stones," can best be gathered from a valuable “ Note"
the present standpoint; the excavations produced clear by Prof. Judd which accompanies Prof. Gowland's evidence touching the mode of crection. Prof. paper. These blue stones are entirely unconnected Gowland's memoir deals only with the leaning stone, with the local geology ; they must, therefore, repre- but I take it for granted that the same method was sent boulders of the Glacial drift, or they must have emploved throughout. This method was this :I Hills Arshacological and Natural History Magazine, xxi. pp.
(1) The ground on the site it
to occupy 141-149.
was removed, the chalk rock being cut into in such a
manner as to leave a ledge, on which the base of the
GEOLOGY OF THE MOON. stone was to rest, and a perpendicular face rising from it, against which as a butiress one side would bear for many years past geologists have turned wistbottom this
fully a clined plane was cut to the surface, down which the study of its surface some insight into planetary evolumonolith which had already been dressed was slid tion, and more especially into some of the stages in the until its base rested on the ledge.
history of our own globe. It must be confessed, how(2) It was then gradually raised into a vertical posi- ever, that as yet few satisfactory data have been obtion by means first of levers and afterwards of a tained, either in the facts observed or in the deductions ropes. The levers would be long trunks of trees, to drawn from them. The great majority of those who one end of which a number of ropes were attached have studied the subject have formed the opinion that (this method is still employed in Japan), so that the our satellite was, once a liquid mass, such as we weights and pulling force of many men might be believe the earth itself to have also been, and that exerted on them. The stronger ropes were probably its so-called “ craters " represent extensive and proof hide or hair, but others of straw, or of withes of longed volcanic activity, when the gases and lava of hazel or willow, may have been in use for minor the heated interior escaped to the surface, probably purposes.
on a scale of magnitude greatly surpassing that on (3) As the stone was raised, it was packed up which subterranean energy has ever been manifested in with logs of timber and probably also with blocks of the geological history of our planet. But another exstone placed beneath it.
planation has been proposed for these lunar features, (4) After its upper end had reached a certain eleva- according to which, as worked out by Mr. G. K.
tion, ropes were attached to it, and it was then hauled Gilbert, of the United States Geological Survey, the by numerous men into a vertical position, so that its moon was formed by the aggregation of a ring of back rested against the perpendicular face of the chalk meteorites which once encircled the earth, and the which had been prepared for it. During this part of “craters," instead of arising from the escape of the operation, struts of timber would probably be volcanic energy from within, were produced by the placed against its sides to guard against slip.
impact of the last meteoric bodies that fell from As regards the raising of the lintels, and imposts, without. These bodies, arriving with planetary and the placing of them on the tops of the uprights, velocity, would be melted or reduced to gas, while there would be even less difficulty than in the erection a portion of the lunar surface around them would of the uprights themselves.
also be liquefied. Mr. Gilbert believes that the lunar It could be easily effected by the simple method topography bears witness to such a meteoritic bompractised in Japan for placing heavy blocks of stone in bardment rather than to gigantic volcanic explosions. position. The stone, when lying on the ground, would The latest contribution to the discussion was be raised a little at one end by means of long wooden recently presented to the Academy of Sciences of levers. A packing of logs would then be placed under Paris by MM. Lewy and Puiseux. These eminent
1 the end so raised, the other extremity of the stone astronomers direct attention to the evidence furnished would be similarly raised and packed, and the raising by the latest photographic charts of the “. Atlas and packing at alternate ends would be continued Lunaire" in regard to the conditions in which a until the block had gradually reached the height of planetary body passes from the liquid to the solid state, the uprights. It would then be simply pushed forward and to the stage in this transformation which has by levers until it rested upon them.
been reached respectively by the earth and the moon. I shall deal later on with several interesting con- With respect to the evolution of the earth two clusions to which these investigations lead.
opposite theories have been propounded. The great NORMAN LOCKYER.
body of geologists have maintained that the interior
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