By Nevil Story Maskelyne, M.A., P.R.S. 151 
ave formed, and the ingenuity and exertion of power that collected 
them from far and wide, on a single spot upon the plain, are hardly 
more remarkable than the art which dressed and shaped their uncouth 
forms into those squared and mortised megalithic masses, the material 
of which is among the hardest known varieties of rock. Regarding 
another of these four varieties of Stonehenge rock * Professor 
Phillips was no doubt correct in his forecast. He asserted the so- 
called altar-stone to be “a grey sandstone composed of quartz sand, 
silvery mica, and some dark grains (possibly hornblende) ;” and he 
added that “such a stone might be obtained from the Devonian or 
gray Cambrian rocks—and in other situations.” In fact there are 
layers in the old red sandstone that might furnish the counterpart 
of the so-called altar-stone. My valued assistant at the British 
Museum, Mr. Thomas Davies, to whose aid in this, as in other in- 
vestigations where I have sought it, ] am in many ways greatly in- 
debted, has cailed attention to the occurrence of just such a rock at 
the top of the old red sandstone cropping out no further off than 
Frome. 
It may not perhaps be entirely irrelevant to remark that the 
Scone stone in Westminster Abbey is composed of a very similar but 
somewhat darker coloured rock. The opportunity was once offered 
me by the Dean of Westminster, in company with Professor Ramsay, 
of scrutinising that stone. ‘Tradition, for once probably correct, 
traced its history back to Dunstaffnage, which most venerable of the 
Royal castles stands just where a small patch of old red sandstone 
shows itself; and no doubt the Dunstaffnage sandstone is the parent 
rock of the “ Stone of Destiny.” 
There remain to be considered the two rocks which compose the 
whole that survives of the two kinds of smaller Stonehenge stones. 
It is here that I shall have to differ in some points from those who 
have gone before me. With regard to one of these, and that the 
larger group, the terms greenstone and even syenite have been 
1See Mr. William Long’s exhaustive monograph on ‘Stonehenge and its 
Barrows, 
