August 4, 1898] 



NATURE 



329 



between the general terms of recurring series and the elements 

 which define them. This subject he treats by a new method, 

 involving a generalisation of the isobaric algorithm, and a 

 number of interesting applications form a noteworthy feature of 

 the paper. 



A METHOD of determining simultaneously the electric and 

 thermic conductivities of metals at different temperatures is 

 described by Signor Paolo Straneo in iht Aitidei LJncei,y'\\. II. 

 The principal object of the experiments was to ascertain how 

 the thermic conductivity of a substance varied with the tem- 

 perature. As regards the internal conductivity, the variations 

 were found to be too small to be determinable to a sufficient 

 degree of precision by existing methods. The coefficient of 

 surface conductivity increases with the temperature, and the 

 dispersivity not only increases with the absolute temperature, 

 like the coefficient of specific heat, but is at least a quadratic 

 function of the difference of temperature between the body and 

 the surrounding air. 



The so-called chromatolysis, supposed by Ca vara to exist nor- 

 mally in the nuclei of plants, is discussed in the Atti dei Lincei 

 by Dr. B. Longo, who enunciates the following conclusions : 

 (i) The phenonomen of chromatolysis does not exist in the 

 normal vegetable nucleus ; (2) the nucleoli consist of one 

 unique substance, and not of a central one representing the 

 nucleolus proper of Cavara, and a peripheric one representing 

 the chromatin ; (3) the nucleolus proper of Cavara is nothing 

 but a vacuole ; (4) the nucleoli are either perfectly homogeneous 

 r vacuolate, but never alveolate; (5) in the present state of 

 ience we are ignorant of the true function of nucleoli. 



Prof. G. Mercalli has recently prepared an important 

 memoir on the earthquakes of southern Calabria and the district 

 around Messina {Mem. della Soc. Ital. delle Scietize, ser. iii. vol. 

 xi.). The first part contains a catalogue of all the shocks felt 

 in this region from 1169 to the present day. In the second, a 

 special study is made of the more important seismic series, and 

 especially of that which commenced on February 5, 1783. Of 

 this series alone (1783-86), the author adds notices of about 500 

 shocks to the 1186 already chronicled by Vivenzio and Pignatari. 

 The most interesting part is, perhaps, the third, which deals 

 with the recent series of earthquakes beginning on November 

 16, 1894, the origin of which Prof. Mercalli traces to two centres, 

 one in the sea of Palmi, the other beneath the western slope of 

 Aspromonte, between S. Cristina and Delianova. Among the 

 general conclusions formulated are the following :— TheCalabro- 

 -Mcssinese earthquakes, as a rule, occur in long series. The 

 great destruction caused by those of 1783 was due not only to 

 the violence of the shocks, but especially to their long duration 

 (two minutes and more), and to the nature of the surface rock- 

 formations. All the great earthquakes of the district are inde- 

 pendent of the volcanic foci of Etna and the Aeolian island*, 

 there being about eighteen different, seismic centres. With 

 regard to the causes of the earthquakes, the author considers 

 tectonic dislocations insufficient, and would prefer either masses 

 of water passing instantaneously into the state of vapour, 

 laccolitic or plutonic displacements and injections, or subter- 

 ranean rock-falls. On account of their position and supposed 

 origin, he proposes to apply the term inter-volcanic to the 

 Calabro-Messinese earthquakes. 



The Report of Mr. J. C. Willis, director of the Royal 

 Botanic Gardens, Ceylon, on the condition of the Gardens, and 

 the work accomplished during 1897, records a number of inter- 

 esting points. The appointment of Mr. E. Ernest Cireen as 

 Honorary Government Entomologist is noteworthy. As to the 

 work of the Gardens, a fair amount of ground was laid out 

 NO. I 50 1, VOL. 58] 



during the year in experimental plots of economic plants, 

 chiefly at Peradeniya. An attempt was made to bring the de- 

 partment more into touch with the public by issuing periodical 

 circulars dealing with horticultural, agricultural, and botanical 

 subjects. Each circular deals with one subject only. Three 

 were published during the latter half of 1897, one being intro- 

 ductory, the others dealing with the cacao disease. Copies are 

 sent free to all Government officers, to planters' associations 

 and similar bodies, and to botanic gardens and similar institu- 

 tions abroad. Much attention was given during the year to 

 the cacao canker. During the early part of the year an ex- 

 tended investigation of the diseased areas was made, and the 

 disease was found to be common in nearly all parts of the 

 Central and Uva Provinces. The disease was found to be due 

 to the attack of a fungus, whose exact nature is at present 

 unknown, but which almost certainly belongs to the class of 

 fungi which cause the various cankers of stems and roots. The 

 interest taken in the cultivation of Para rubber received a very 

 great impetus during the year, and the demand for seed was 

 enormously larger than the supply. The total crop of seeds 

 from mature trees in the Gardens was rather over 100,000 seeds, 

 of which 88,500 were sold to planters in Ceylon. The cultiva- 

 tion of camphor trees is also full of promise. It is reported 

 that camphor plants continue to grow well at Hakgala, some of 

 them being nine feet high. Of the plants distributed in 1895, 

 some of those in Galle District have grown to a height of twelve 

 feet. In the laboratory attached to the museum, researches 

 were carried on during 1897 by several European investigators. 

 The work of the Gardens has thus been for the advancement of 

 pure as well as economic botany. 



A LARGE amount of work is being done in the various 

 American botanical laboratories on the embryology of flower- 

 ing plants, and interesting results have in several cases been 

 obtained. Among the more recent contributions are one on 

 the Pontederiaceas (Pontederia and Eichchornin), by Wilson 

 R. Smith ; the results being very similar to those with other 

 Monocotyledons of a low type, such as Naias and Zanni- 

 chellia ; and one on Euphorbic corollata, by Florence May 

 Lyon. The embryo of this plant is characterised by the 

 extremely long synergids, and the very temporary character of 

 the antipodals. The work was in both instances done in the 

 Hull Botanical Laboratory. We have also received P.irt i. of 

 the second series of the Minnesota Botanical Studies ; and 

 three publications from the U.S. Department of Agriculture: 

 a Preliminary Report of the Soils of Florida, by Milton 

 Whitney ; and Nutrition Investigations at the University of 

 Tennessee and in Pittsburg respectively, by Dr. Charles R 

 Wait and Prof. Isabel Bevier. 



The special correspondent of the Lancet in Calcutta writes r 

 " A very diplomatic compromise between what ought to be 

 done and the wishes and prejudices of the natives has been- 

 effected in Calcutta by the establishment of licensed family- 

 hospitals for plague cases. The sanitary measures hitherta 

 adopted elsewhere are not adapted to the Indian people, and 

 consequently the regulations about plague have been evaded ia 

 every possible way. The establishment of this system, there- 

 fore, has gained the confidence of the people. Besides the 

 public hospitals and the ward hospitals there are numerous 

 private hospitals, so that all the communities are now well 

 provided for. In addition to this, houses possessing anything 

 like suitable accommodation for the isolation of a case of plague 

 are allowed to have one or more rooms sat apart for the purpose. 

 By these concessions every case of plague ought to come under 

 observation. The plague scare has greatly subsided, and 

 inoculation is coming slowly into favour among all classes." 



