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their inscriptions legible for a century or longer. But even in these 
cases the progress of internal disintegration is distinctly visible. 
Where the marble has been less screened from rain, the rapidity of 
waste has been sometimes very marked. A good illustration is 
supplied by the tablet on the south side of Greyfriars’ Churchyard, 
erected in memory of G G , who died in 1785.* This 
monument had become so far decayed as to require restoration in 
1803. It is now and has been for some years for the most part 
utterly illegible. The marble has been dissolved away over the 
centre of the slab to a depth of about a quarter of an inch. Yet this 
monument is by no means in an exposed situation. It faces east- 
ward in a rather sheltered corner, where, however, the wind eddies 
in such a way as to throw the rain against the part of the stone 
which has been most corroded. 
In the majority of cases superficial solution has been retarded by 
the formation of a peculiar grey or begrimed crust, to he immediately 
described. The marble employed here for monumental slabs appears 
to be peculiarly liable to the development of this crust. Another 
kind of white marble, sometimes employed for sculptured ornaments 
on tombstones, dissolves without crust. It is snowy white, and 
more translucent than the ordinary marble. So far as the few 
weathered specimens I have seen enable me to judge, it appears to 
be either Carrara marble, or one of the strongly saccharoid, somewhat 
translucent, varieties employed instead of it. This stone, however, 
though it forms no crust, suffers marked superficial solution. But it 
escapes the internal disintegration, which, so far as I have observed, 
is always an accompaniment of the crust. Yet the few examples 
of it I have met with hardly suffice for any comparison between 
the varieties. 
(2.) Internal Disintegration . — Many of the marble monuments in 
our older churchyards are covered with a dirty crust, beneath which 
the stone is found on examination to be merely a loose crumbling 
sand. This crust seems to form chiefly where superficial solution is 
feeble. It may be observed to crack into a polygonal network, the 
individual polygons occasionally curling up so as to reveal the 
yellowish white crumbling material underneath. It also rises in 
* For obvious reasons I withhold the names carved on the tombstones 
referred to in this communication. 
