July ii, 1895] 



NA TURE 



251 



of high scientific standing, and that the licencees are persons 

 who, by their training and education, are fitted to undertake 

 experimental work and to profit by it. All the experimental 

 work has been conducted in suitable places ; the number of 

 experiments performed was 3104. In more than one-third of 

 these the animal suffered no i)ain, because complete anjesthesia 

 was maintained from before the commencement of the experi- 

 ment until the animal was killed. More than fifteen hundred 

 of the remaining experiments were of the nature of hypodermic 

 injections or inoculations. In about five hundred experiments 

 the animal was anivsthetised during the operation, but was 

 allowed to recover. These operations, in order to insure success, 

 are necessarily done with as much care as are similar operations 

 upon the human subject : and the wounds being dressed anti- 

 septically, no pain results during the healing process. 



TllK Geologists' Association will visit the coast of Antrim 

 and the Mourne Mountains this summer (July 29 to August 3). 

 The programme includes the examination of sections in sedi- 

 mentary rocks ranging from the Ordovician to the Chalk, pre- 

 Devonian gneisses, and the basalts, rhyolites, and drusy granites 

 of the Tertiary eruptive series. The illustrative papers by 

 Messrs. McHenry and Lloyd Praeger will shortly be issued as 

 a pamphlet, in advance of publication in the Proceedings. The 

 country to be visited is classic, and additional interest is added 

 to it by the recent publication of two papers in the Geological 

 Magazine. The first of these, in the June number, by Mr. 

 Mclienry of the Irish Geological Survey, describes valuable 

 evidence as to the age of the trachyte (rhyolite) of the district. 

 In a section at Templepatrick Quarry, the acid lava is seen, by 

 the arrangement of its columnar and flow-structure, to have 

 flowed over the surface of the Chalk, sweeping the overlying 

 gravel before it, and piling it up against the denuded edge of a 

 mass of basalt belonging to the earlier of the two basic series. 

 As fragments of the trachyte occur elsewhere in gravels overlain 

 by the la/er basalts, it may be said to be of " mid-basaltic" age. 

 The second paper, in the July number, is by I'rof. Cole, and 

 deals with the nature of the acid rocks poured out from the 

 Tardree volcano, which are said to equal in variety the better 

 known rhyolites of Hungary. 



TllK numbers of the Botanical Gazette for May and June 

 contain a translation, by Mr. G. J. I'eirce, of Prof. Strasburger's 

 laper on the '• Development of Botany in Germany during the 

 Nineteenth Century." In the latter number there is also a very- 

 instructive article, by Mr. J. .M. Coulter, on the " Botanical 

 Work of the American (jovernment." .\t present four distinct 

 divisions of botanical work are organised under the Department 

 of .Vgriculture, although other divisions also do a certain amount 

 of work that may fairly be called botanical. These four divisions 

 are those of botany, vegetable physiology, and pathology, 

 agrostology, and forestrj-. The Division of Botany, under the 

 general supervision of Prof. Y. \. Coville, of Cornell University, 

 is engaged in strictly scientific work, such as the working out of 

 local floras, the examination of seeds, investigation of weeds, i\:c. 

 To this department the Government appropriates, during the 

 l.rcscnt year, 33,800 dollars. The division of vegetable physi- 

 ology and pathology (26,300 dollars) is concerned with 

 investigations into the phenomena of the growth of plants, and 

 into the diseases of cultivated plants. Its chief is Prof. B. T. 

 Galloway, University of Missouri: but investigations on behalf 

 of the department are carried on also at the following centres : — 

 University of Nebraska, University of Michigan, University of 

 Illinois, Kansas Agricultural College, University of Copenhagen. 

 The function of the Division of .\grostology (15,000 dollars) is 

 to deal with forage plants as well as grasses, to instruct and 

 familiarise the people with the habits and uses of these plants, 

 to condvict investiga'.ions relative to their natural history and 

 NO. I 34 1, VOL. 52] 



adaptability to diffierent soils and climates, to introduce promising 

 native and foreign plants into cultivation, and to identify grasses 

 and forage plants. Its chief is Prof. F. Lawson-Scribner. The 

 Division of Forestry, under the charge of Mr. B. E. Fernow, 

 has at present chiefly been occupied with the study f)f 

 character and value of different timbers. 



The current number of ihc: Journal tie Pliysii/ne contains the 

 second part of the paper, by M. P. Curie, on the magnetic 

 properties of bodies at difierent temperatures (see X ATI' RE, 

 June 6, 1895, p. 134). The present paper deals with iron, nickel, 

 and magnetite. In the case of iron, measurements have been 

 made at temperatures between 20' C. and 1360' C, and for field 

 strength of from 25 to 1350 C.tl-.S. units. The observations on 

 nickel and magnetite were only made at temperatures above that 

 at which the great change in the magnetic properties of these 

 bodies takes place. The values obtained with iron up to about 

 756' C. agree with those previously obtained by Dr. Hopkinson. 

 Above this temjierature the author finds that the curves showing 

 the relation between the intensity of magnetisation (I) and the 

 strength of the field are straight lines passing through the origin 

 for temperatures between 750° and 1280° F. decreases more and 

 more slowly. At first (I) decreases to half its value for a rise of 

 temperature of a few degrees, but between 950° and 1280° the 

 susceptibility is almost a constant, only decreasing very^ little as 

 the temperature rises. At a temperature of about 1280' the 

 susceptibility suddenly increases by about 50 per cent., and then 

 again gradually decreases up to 1365". The author, with some 

 hesitation, gives the following explanation of this behaviour : — 

 " Up to a temperature of 860° iron behaves like any other- 

 paramagnetic bod)'. At a temperature of about 860°, however, 

 it begins to change into a second allotropic form, this trans- 

 fonnation being complete at about 920 \ and the iron remaining 

 in this condition up to 1280°, and behaving like such a body 

 as oxygen or palladium. Finally at 1280" the iron changes 

 suddenly back to its first condition." The attractiveness of the 

 above theory can only Vje appreciated by a study of the author's 

 curves, for if the curve showing the connection between the 

 logarithm of the susceptibility and the logarithm of the tempera- 

 ture is plotted, it is found that the curve between 750° and 

 860' would, if prolonged, form with the curve above 1280° a 

 curve in all respects similar to the curves obtained in the case of 

 nickel and magnetite. With nickel the author finds that the 

 temperature of the magnetic transformation is about 340°. After 

 this temperature the susceptibility is independent of the strength 

 of the field, and decreases regularly and very rapidly as 

 the temperature rises. In the case of magnetite the chief 

 magnetic transformation takes place at a temperature of 535°. 

 Ai temperatures between 550^ and 1370' the susceotibilily 

 is independent of the strength of the field, and decreases 

 regularly, and between 850° and 1360' varies inversely as 

 the absolute temperature. The value of K (see previous 



note, he. cit.) being given by the expression K = „ - where 



T is the absolute temperature. From the differences exhibited 

 by the behaviour with change of temperature of diamagnetic 

 and paramagnetic bodies, the author considers that these two 

 properties must be attributed to different causes. 



L.\si' week the Pharmcueulieal Journal began the first 

 of a new and enlarged series (the fourth). The journal, 

 which is now in its fifty-fifth year, has done much to promote 

 pharmaceutical organisation and progress. 



Tm. second part of the Report of the International Meteoro- 

 logical Congress held at Chicago in 1S93, has just come to us 

 from the United States Deiiartment of Agriculture (Weather 

 Bureau). The papers included in the Report were communicated 



