sea Dr. Richardson’s Letter on the basaltic Surface 
strata ; in ail these cases the change is always per saltum and 
never per gradus, the lines of demarcation always distinct, and 
well defined ; yet the different materials pass into each other 
without interrupting the solidity and continuity of the whole 
mass. 
6. The facades on our coast are formed as it were by ver- 
tical planes, cutting down, occasionally, the accumulations of 
our strata ; the upper part of these faqades is generally per- 
pendicular, the lower steep and precipitous. 
7. The bases of our precipices commonly extend a con- 
siderable way into the sea ; between the water and the foot 
of the precipice, (and especially near the latter) there is fre- 
quently exhibited the wildest and most irregular scene of 
confusion, by careless observers supposed to be formed by 
the ruins of the precipice above, which have fallen down ; 
such, no doubt, was Mr. Whitehurst’s idea, when he de- 
scribes one of these scenes as “ an awful wreck of the terra- 
queous globe.” 
But a more attentive observer will soon discover that 
these capricious irregularities, whether in the form of rude 
cones, as at Beanyn Daana, and the west side of Pleskin; 
or towers, as at the dyke of Port Cooan and Castro Levity at 
the foot of Magilligan faqade, even spires and obelisks, as to 
the westward of Kenbaan, and at the Bull of Rathlin ; yet all 
of these once formed part of the original mass of coast, 
stratified like it, and their strata still correspond in material 
and inclination with those in the contiguous precipice. 
8. These vertical sections or abruptions of our strata are 
by no means confined to the steeps that line our coast ; the 
remaining boundary of our basaltic area has several of them 
