162 Maclure’s Letters. 
ed to have claims to the soil, and who would not permit a 
rock to be taken from it, or any depredation, as they termed 
it, to be committed. I now send you a small box of speci- 
mens, though imperfect, from the constant rain during my 
stay at the Causeway. They may serve as a comparison 
with others, although I do not perceive any great difference 
from other Basaltic regions which | have seen, except the 
articulations of the pillars, which are peculiar to the Giant’s 
Causeway. The same arrangement, in ridges Jong and nar- 
row in proportion to their length, the porous rock always on 
the summit of the ridge, and the compact Basalt at the bot- 
tom. Where they come in contact with any combustible, such 
as coals, these are charred from three to four feet from the 
junction, &c. &c. &c. Through all this country.the Basalt 
generally covers a stratum of white limestone, filled with 
ints. with much the same petrified shells as are to be found 
in the chalk. 
I have left the box W. M. No. 21, with Mr. James M’Adam, 
-avery active member of asocicty lately established here for 
Natural History, and supported by a number of industrious 
young men, who will forward it to New-York, care of Col. 
Gibbs. If you consider it useful to the Geological Society 
to have one of the pillars of articulated Basalt, or any other 
mineral this country can afford, by your forwarding them a few 
du>licate specimeas, desiring them to make a return of what 
you require, | have no doubt but an exchange mutually be- 
neficial might be established, as it is a society in a state of 
progressive improvement, which promises much; and being 
composed of young men, unincumbered with the prejudices 
of age, more may be expected from them than from old soci- 
eties confined within the limits of etiquette and formality. 
I am highly gratified with the progress of civilization in 
this country, more particularly in this place, in which the im- 
provement has been, and still continues to be rapid, and which 
resembies more a townin the United States, for new streets and * 
houses, than any place | haveseenin Europe. The attention 
of many of the most liberal and influential men to the edu- 
cation of the millions of the productive class, is more than I 
expected to find any where in aristocratic Europe. The im- 
provement of old, and the establishiny of new schools, shows a 
public spirit well directed, that ought to be imitated by no 
country more than our own. Wh ee the general mass rules, 
the diffusion of knowledge is positively necessary for the 
