164 



SCIENCE-GOSSIP 



[July 1, 1866. 



Wood Anemone {Anemone nemorosa). — In a 

 plainly-written little book lately published, entitled 

 "The Every-Day Book of Natural History," the 

 following passage occurs in an article on the 

 Wood Anemone : — " The blossom of the plant is suc- 

 ceeded by clusters of minute seeds, with long shining 

 curious tails, that have a very peculiar appearance 

 when waving in the wind" (p. 140). I would just 

 mention, for the benefit of young beginners in 

 botany, that this "very peculiar appearance " exists 

 only in the author's imagination, as the seeds of A. 

 nemorosa are destitute of " tails" the Pascpie-flower 

 • {A. Pulsatilla) being the only British anemone 

 which exhibits them. — B. 



Drying Speedwells. — After reading the excel- 

 lent article on " speedwells," I recollected seeing 

 the germander speedwell {Veronica Chameedrys) 

 dried, so as to retain its colour, by one of my family, 

 who is just now busily employed in collecting the 

 weeds and native plants around us. Her method of 

 preserving them is this : — she carefully places the 

 specimen between two sheets of blotting paper, 

 filtering paper is better for some plants, and with a 

 common flat iron, such as used in the laundry, she 

 presses it until it remains perfectly even upon the 

 paper, and then removes it to her collection. The 

 iron must be moderately heated, and the plant well 

 protected. I have often seen the ordinary method 

 of drying succeed, if the following rule is observed : 

 — always flatten the veins, stalks, &c, with the 

 thumb nail, or an ivory paper cutter. This pre- 

 vents the air permeating between the sheets of paper 

 and causing the colour to change. 



Cluster Cups. — During a recent trip into Norfolk 

 I found the dock cluster cups {JEcidkim rubellum) 

 exceedingly common, not only on dock and sorrel, 

 but also on rhubarb leaves. The honey-suckle 

 cluster cups {JEcidium periclymeni) were also plen- 

 tiful. Both species are rare in the neighbourhood 

 of London. I also discovered, in a marsh belong- 

 ing to Mr. S. B. Cooke, of Dilliam, a species new to 

 this country, on the leaves of an orchis ; this is the 

 JEcidium orcliideurum, Eiedl. In the same spot 

 several specimens of JEcidium pedicularis, another 

 rare species, were found. At Horstead, as well as 

 in the neighbourhood of Bungay, and probably else- 

 where, JEcidium quadrifidum is found on the leaves 

 of the garden anemone. — 31. G. Cooke. 



Sunflower. — The annual sunflower {Helianthus 

 animus) is first mentioned in this country by Gerard, 

 who notices it in the year 1596, under the name of 

 "The Flower of the Sunne, or the Marigolde of 

 Peru." 



Ferns of Java. — In Blume's "Enumeration," 

 no less than 460 species are described, of which 

 about 300 are regarded as new. — Smith's Ferns, 

 British and Foreign. 



PHOTOGRAPHIC GOSSIP. 



The Permanence of Photographs.— However 

 doctors may differ as to why photographs commonly 

 fade, they are tolerably well agreed as to the fact 

 that they do so fade, and very few, therefore, will 

 fail to hail with profound satisfaction a discovery 

 which removes what, by universal consent, is 

 regarded as the source of destruction, viz., the 

 presence of hyposulphites in the finished print. 

 The discovery in question we owe to Dr. Angus 

 Smilh, F.R.S., who has pointed out that, by using 

 a weak solution of peroxide of hydrogen, the hypo- 

 sulphites which may be locked up from mechanical 

 action in the size of the paper may be decomposed 

 into the sulphates, which are held to be harmless. 

 By adopting this plan— and already the photographic 

 chemists find a growing demand for this new com- 

 pound springing up, there is every reason for believ- 

 ing that photographs will, at last, be rendered 

 permanent. Mr. Dawson, of King's College, who 

 is usually first in the field when the value of any 

 new discovery is to be tested and reported on, has 

 carried 'out numerous excellent experiments, all 

 tending to illustrate the immense value of this novel 

 photographic agent, by demonstrating not only the 

 impossibility of removing every trace of the hypo- 

 sulphites from sized paper, but also the permanence 

 of prints treated with the per-oxide in question. 

 According to this gentleman's experience one fluid 

 ounce of a ten-volume solution of peroxide of 

 hydrogen, diluted with one quart of water, will 

 convert into the sulphates the sulphites contained 

 in four full size sheets of photographic paper (IS x 

 22) after they have been thoroughly washed in the 

 usual way. 



Photographing the Pyramids.— The Astro- 

 nomer Royal for Scotland has brought home from 

 Egypt some of the most interesting mementoes of 

 his visit in the shape of some very small but sin- 

 gularly perfect photographs, which, when recently 

 enlarged and thrown upon the screen at a public 

 meeting in Edinburgh, astonished and delighted 

 those present in no small degree. The negatives 

 obtained by the wet process, necessarily, are but 

 one inch square in size, yet they bear magnifying up 

 to fifteen feet without apparent loss of sharpness or 

 distinctness, and when we consider the difficulties 

 with which Professor C. Piazzi Smith had to contend, 

 this amount of perfection appears the more remark- 

 able. These were— a temperature of 90° ; — the 

 minute particles of sand with which the atmosphere 

 was loaded, which rendered necessary a special 

 mode of preparing and exposing the plates, and the 

 necessity of having to prepare the plate some time 

 before it could be exposed, and keeping it some 

 time before it coidd be developed, together with 

 other technical difficulties, forming a long and for- 

 midable list- J. W. W. 



