286 Mr. Weaver on the Structure of the South of Ireland^ 
the Slievenamuck and the other ranges more west, which rise 
in the vale of Limerick (although in fact all connected and 
belonging to the same formation), are alone coloured as old 
red sandstone (reddish and yellowish-brown*.) 
A few remarks here upon the construction of sections may 
not be misplaced. In my sections through the south of Ire- 
land I have endeavoured to combine two objects, namely, to 
give outlines of the actual forms of the surface presented by 
nature, and to represent faithfully the relative position of the 
successive mineral masses, employing as nearly equal scales 
for heights and distances as the engraving would permit, the 
difference being only as four to three; but I have not at- 
tempted to introduce the differently modified structure of 
their respective stratification, and for two reasons ; ] st, that 
to do it correctly upon any given transverse line according 
to scale and measure, would require considerable labour, and 
even when accomplished might not exactly accord with the 
results of an examination conducted on parallel lines in differ- 
ent longitudes, in a country where the stratification is more 
or less fluctuating ; 2nd, that unless done correctly, such sec- 
tions, instead of conveying precise information, tend rather to 
mislead the judgement. In such cases, it appears more judi- 
cious to supply tlie deficiency by adequate description. 
Now, it is for the second of these reasons that I must ob- 
ject to Mr. Griffith’s sections. They appear to me in many 
respects drawn rather according to the conceptions of their 
author than the occurrences in naturef. As some proof of 
this, I will in the first instance take the section which is 
drawn through the south-eastern part of the island, beginning 
at the valley of the Suire (where it first intersects the car- 
boniferous limestone), and following it to its extremity in the 
* In the new map the Gaultees are now also coloured reddish brown, as 
old red sandstone. 
t The same remark applies to the sections drawn in Kerry by Mr. C. 
W. Hamilton also, but especially so to the section No. 3 in his ‘'Outline 
of the Geology of part of the county of Kerry,” in the Journal of the Geo- 
logical Society of Dublin, vol. i. pp. 276 to 285, in which there is nowhere 
drawn a clear distinction between the conglomerates and sandstones of the 
transition series and those of the old red sandstone formation, the one 
being confounded with the other. Moreover, in No. 3 section, the old red 
sandstone and the coal measures are confounded together, the latter 
(north of Tralee) being made to underlie and break through the carboni- 
ferous limestone instead of reposing upon it, and the text in p. 284 is to 
the same effect. This is the paper referred to by Prof. Sedgwick and Mr. 
Murchison in the Lond, and Edin. Pliil. Mag. in April 1830, at p. 260, and 
to which I had occasion to advert in the same Magazine for August, 1839, 
at p. 122. Two later sections in Kerry, given by Mr. C. W. Hamilton in 
the Lond. and Edin, Phil, Mag, for Dec. 1839, are not only open to the 
