148 



NA TURE 



[June 14, 1900 



the question of geological age, we agree with Nathorst's 

 verdict that the plant-bearing beds must be assigned 

 either to an Upper Jurassic or to a Lower Cretaceous 

 horizon. Several of the plants suggest a comparison 

 with Inferior Oolite species from the rich plant-beds of 

 the Yorkshire coast, and it is not improbable that in the 

 fragmentary fossils from Cape Flora we have the re- 

 mains of a flora but slightly younger than that which 

 has left abundant traces in the Lower Oolite strata of 

 more southern latitudes. While admitting the danger of 

 attempting to assign an exact geological date to the 

 fragmentary and imperfect specimens, there can be no 

 doubt that they must be referred to a period anterior to 

 the Tertiary, and in all probability they are remnants of 

 an Upper Jurassic flora. 



While regretting that the fossils from Franz Josef 

 Land are not more numerous and less fragmentary, we 

 may offer a hearty welcome to the two able palseontolo- 

 gical memoirs by Dr. Pompeckj and Prof. Nathorst ; 

 these authors, in carrying out their difficult tasks with 

 thoroughness and good judgment, have set a standard 

 of efficiency which promises well for the succeeding 

 volumes of the " Scientific Results " of the Nansen 

 Expedition. A. C. S. 



As might have been expected, no birds new to science 

 were obtained during the voyage of the Fram ; never- 

 theless, some interesting observations were made on the 

 range and distribution of bird-life in the high north, while 

 naturalists have, apparently for the first time, been made 

 fully acquainted with the early plumage of the roseate gull. 

 In the course of the expedition birds were observed in the 

 highest latitudes in which they are definitely known to 

 be able to exist. During the summer of 1895, when the 

 vessel was between 84° and 85^ 5' north lat., in the neigh- 

 bourhood of Franz Josef Land, ten species were from 

 time to time observed, although none occurred in any 

 numbers. The one found farthest north was the Fulmar 

 petrel, which was seen in lat. 85° 5' ; in the last edition 

 of " Yarrell " the extreme range of this bird is given 

 as 82° 30'. 



During the summer of 1896, when the Fram was 

 north of Spitzbergen, the first herald of returning bird- 

 life was a snow-bunting, which made its appearance on 

 April 25. From the observations made during the same 

 season, it is now evident that to the north of Spitzbergen, 

 between lat. 81° and 83°, the Arctic Ocean is the resort 

 of large numbers of birds, belonging, however, to com- 

 paratively few species. Apparently these consist for the 

 most part of immature individuals, in the first plumage, 

 which spend the summer among the open channels in 

 the ice. The little auk and the ivory gull were among 

 those most numerously represented ; Sabine's gull having 

 only been seen on a single occasion. Although swimming 

 birds were by far the most numerous in these high lati- 

 tudes, shore-haunting species were represented by the 

 ringed plover and the grey phalarope, which were seen 

 running about on the ice by the side of the open water. 



The fasciculus is illustrated by an artistic plate of the 

 roseate gull in its first plumage, which is mainly brown 

 on the upper-parts, and therefore quite unlike that of 

 the adult. R, L. 



NO. 1598, VOL. 62] 



THE CYANIDE PROCESS. 



The Cyanide Process of Gold Extraciiofi. By James 

 Park. Pp. viii-M27. (London : Griffin and Co., Ltd., 

 1900.) 



THE great success which has attended the introduc- 

 tion of potassium cyanide for the extraction of 

 gold has created a widespread interest in this chemical 

 process, and given rise to several books and papers on 

 the subject from various authors. When we consider 

 that at one large works 500 tons of gold are treated in 

 twenty- four hours, we understand on what a colossal 

 scale the cyanide method is worked. The process, like 

 many others, has grown up from small beginnings, and 

 it is largely owing to Messrs. MacArthur and Forrest 

 that cyanide of potassium is now successfully applied to 

 the treatment of gold ores in different parts of the world. 



It is a most significant] sign of the times that men 

 who have been practically engaged in an enterprise are 

 willing to communicate the results of their experience 

 to the public at large, and from the manner in which 

 the literature of the subject is growing, every detail 

 requisite for economic working will soon be widely 

 known and utilised. Therefore, one is not inclined to 

 analyse the text too minutely, with the object of finding 

 small flaws, provided the information is broadly reliable 

 and accurate. It was inevitable that electricity should be 

 brought into play in connection with such an important 

 process, and we find Messrs. Siemens and Halske early 

 in the field, with a method of depositing the gold on 

 lead by means of electrolysis. There are two sides to 

 this subject, as to most others, viz. the economic, or 

 practical as it is termed, and the scientific. Now the 

 former seems to be fairly well treated, but what is wanted 

 is much greater attention to be paid to the latter, as it 

 is possible that, with fuller and more intimate knovledge, 

 potassium cyanide may be equally useful in the treat- 

 ment of other metals besides gold, especially as it is now 

 so largely used in the electro-deposition of gold, silver, 

 copper, brass, &c. The work under notice has passed 

 through three editions in New Zealand, and this is the 

 first English edition. It is intended for the use of 

 students, metallurgists and cyanide operators. Several 

 new illustrations and tables are added, and the inform- 

 ation relating to the treatment of slimes and the analysis 

 of solutions has been greatly extended. It is gratifying 

 to learn that wet crushing and cyanide treatment have 

 been followed with as much success in New Zealand 

 as in South Africa, although the ores are of a complex 

 character. 



The arrangement of the contents of the book is admir- 

 able. After a brief introduction and a general statement 

 as to the limitations of the subject, the chemistry of the 

 subject is wisely introduced, so that the student is at 

 once brought face to face with the various reactions that 

 occur, and led to see the reason for loss of cyanide, 

 which is sometimes so excessive. Valuable inform- 

 ation is given on pp. 10-13 on the action of potassium 

 cyanide on metallic sulphides. A very useful chapter 

 on laboratory experiments will be appreciated by teachers 

 and students of metallurgy, as well as by the chemist 

 and works manager ; indeed, a commodious and well- 



