March io, 1898] 



NATURE 



437 



I hope-that B may give some measure of absorption, and A — B 

 some measure of dew. 



I reckon grammes of weight gained as cubic centimetres of 

 water, divide this number by the number of sq. cm. in the cir- 

 cular opening, and take the quotient thus obtained as the measure 

 in linear cm. of dew as rain. 



I shall be greatly obliged if any readers can refer me to 

 previous experiments that have been made in this direction. 



Harpenden. T. Wilson. 



Oat Smut as an Artist's Pigment. 



With regard to Prof. Marshall Ward's note under this head- 

 ing (p. 389, ante), I may add that, according to Mr. K. Miyabe, 

 the olive-brown spores of Ustilago es- 

 <ulenta (" Makomo-zumi " in Japanese), 

 besides its application to the painting of 

 the ladies' eyebrows in Japan, are mixed 

 up with oil and smeared on the scalp and 

 hairs by older women who have the hairs 

 thin or grey. " At present," the author 

 adds, ' ' the spores are largely used in the 

 lacquer industry to produce rusty-coloured 

 wares by mixing them with lac" (Z"-^/" 

 Botanical Magazine, Tokyo, vol. ix. p. 

 197, May 1895). 



KUMAGUSU MiNAKATA. 



Februarj' 25. 



basaltic lavas and ash beds thrown out by the volcanoes 

 which broke out along great fissures in early Eocene 

 times. 



Glacial phenomena admit admirably of registration by 

 photography, and the collection is fairly rich in such 

 illustrations. 



Although RaiT»say many years ago wrote an account of 

 the glaciation of North Wales, comparatively little con- 

 nected work has been since done to elucidate this remark- 

 able example of upland glaciation, while a complete 

 photographic record of it remains to be executed. Some 

 few points have, however, been dealt with, notably by 

 the late J. J. Cole, Messrs. Williamson and Wills, Mr. 



GEOLOGICAL PHOTOGRAPHS. 



THE Committee appointed by the 

 British Association for the col- 

 lection and safeguarding of photo- 

 graphs of geological interest has a 

 good record of work to show for the 

 past year. The entire' collection of 

 1750 prints is now uniformly mounted 

 and deposited in the library of the 

 Museum of Practical Geology at 

 Jermyn Street. Over 350 new prints 

 were received during last year. A 

 new feature has been the formation of 

 a collection of picked duplicates illus- 

 trating typical geological phenomena 

 which, in the form of prints or lantern 

 slides, can be lent to local scientific 

 societies or others desiring either to 

 know what work the Committee is 

 doing, or to help on the work. 



No less than 119 of the new photo- 

 graphs come from Ireland, and the 

 north of that country is now well illus- 

 trated. As is well known, the geology 

 of this region is exceptionally interest- 

 ing as it was the site of a great vol- 

 canic outburst in Tertiary times, and 

 the columnar lavas and sills, the dykes 

 intrusive into chalk and into newer 

 and older rocks, the laccolites, vol- 

 canic necks and ash beds, form a 

 text-book of volcanic geology. One 

 of the most remarkable localities is Cave Hill, near 

 Belfast, where the unconformable junction of the chalk 

 with the lavas has been well exposed by the quarrying 

 operations. 



The remarkable section shown in the annexed figure 

 (Fig. i) is reproduced from an excellent photograph by 

 Mr. R. Welch, of Belfast. Unfortunately the section 

 is now being destroyed by quarrying, so that this photo- 

 graph is the best record we possess of it. It shows an 

 old, steep, pre-Tertiary cliff of chalk which was gradu- 

 ally buried in debris, most of which 'was derived 

 from itself. Both cliff and debris were buried by 



NO. 1480, VOL. 57] 



Pliotographed by Mr. 



R. Welch, Belfast.\ 



Fig. I.— Cave Hill, Belfast. 



VCoPyt ight. 



Godfrey Bingley, Mr. Atchison and others, and their 

 work is in the collection. Good as it is, however, it 

 serves best to show how much in the way of systematic 

 recording there is still left to be done. Some one should 

 set to work with Ramsay's book in hjs hand, visit the 

 localities mentioned, photograph them, and, guided by it, 

 seek out and record a complete account of the glaciation 

 of the entire region ; and he cannot do better than begin 

 on Snowdon. Just opposite Snowdon, on a small hill, 

 Y Foel Perfedd, above Pen-y Pass Hotel, the perched 

 block shown in Mr. Bingley's photograph (Fig. 2), of 

 which a reproduction is annexed, overhangs the Pass of 



