142 The Irish Nafin'alist. July, 



geology, and a range of pale tints for the superficial deposits. 

 We note that the solid geology colours are not always quite the 

 same as those employed by the Survey for the same rocks in 

 the well-known one-inch geological maps of Ireland, nor are 

 the drift colours identical with those of the Dublin sheet 

 issued last 3^ear. An excellent and illuminating novelty is 

 supplied in the shape of two selected horizontal sections drawn 

 on the lower margin of the map — the one across the Lagan 

 valley from the basaltic escarpment to the Silurians, the other 

 across the Silurian uplands from the Permian outcrop at Cultra 

 to the patch of Carboniferous limestone at Castle Kspie. 



In the Memoir, too, we note some differences as compared 

 with that of the Dublin district, which are certainly also 

 improvements. Untrammelled by the existence of a previous 

 Memoir relating to precisel}'^ the same area, which required to 

 be practically reproduced, a general description of the 

 geology of the district, solid and drift, is first given, occupying 

 65 pages. Here the general reader, and the geologist wishing 

 to obtain a broad conception of the geological features around 

 Belfast, is provided with an excellent descriptive account, 

 clear and concise, with references to the more important 

 literature. Following on this, as Part II., comes the detailed 

 description of the drifts, occupjdng 55 pages. Thereafter 

 succeed short chapters on economic geology, petrology, and 

 mineralogy, deep well-sections, and bibliography. This 

 getting together of the general description is distinctly a 

 convenience, for, while the high value of the detailed account 

 and its mass of information is bej^ond question, it appeals to a 

 different audience than that for whom the general account 

 will suffice — namely, to the scientific or the industrial man 

 who is actually at work in the district. While each section of 

 the detailed description is initialed by the officer responsible 

 for it, this general description, occupying nearly half the 

 Memoir, is unsigned, but the Preface tells us that the somewhat 

 unenviable task of abridging the account of all the rocks of 

 the district from the existing Memoirs, and bringing it up to 

 date, without any opportunity of fresh study of the solid 

 geology, has fallen on Mr. I^amplugh. A good deal has been 

 published concerning the district since the appearance in 

 J871-76 of the three Memoirs which deal in part with the area 



