March 7, 1889] 



NATURE 



447 



On January 22, about 2 a.m., an earthquake shock was felt at 

 Honefos, in Central Norway. This was followed by another, 

 and by a few more at intervals, but faint in character. 



A NUMBER of houses were de.«troyed by the earthquake that 

 occurred at Fleurier, in the Jura Mountains, on February 13 



In the American Meteorological Journal iox December last, 

 General Greely, Chief Signal Officer, contributes an interesting 

 article on " Average Velocities of Low-area Storms and Upper 

 Air Currents in the United States." The author shows that the 

 decrease in velocity of the former is regular and unbroken from 

 February to June, and that the increase is nearly as regular to 

 February again. He expresses the important opinion that the 

 average movement of low-area storms in the United States 

 bears a definite relation to the velocity of upper air currents ; 

 and in support of this, a chart is given showing a remark- 

 able accord between the mean hourly velocity of low-area 

 storms and the mean velocity of the upper air currents from 

 1881-87. Prof. M. W. Harrington contributes a useful article 

 in the shape of a translation of a simple demonstration of the 

 deflection of horizontal motion due to the earth's rotation, from 

 Dr. Giinther's " Lehrbuch der Geophysik," without the use of 

 higher mathematics. In the January number, Mr. A. L. Rotch 

 gives a very complete account of the organization of the meteoro- 

 logical service in France since the first establishment of weather 

 telegraphs by Leverrler at the iParis Observatory in 1856, 

 together with descriptions of the instruments and methods now 

 employed. Since 1887 the meteorological service has been 

 separated from the astronomical work, and has been under the 

 able direction of Prof. E. Mascart. Theobserving-station of the 

 Central Office is the Pare St. Maur Observatory, nearly ten 

 miles south-east of Paris. 



In the latest Report of the Bombay Chamber of Commerce, 

 it is stated that it was decided by the Government last May to 

 abolish the office of Meteorological Reporter of Western India, 

 and substitute for it that of Reporter at a reduced salary, who 

 would work under and through the Meteorological Office at 

 Simla. The Chamber, thinking that this alteration would be 

 detrimental to the shipping in the port by stopping the system 

 of storm-warnings that had been carried on for some years, 

 petitioned the Government against the proposed change, and 

 advocated the establishment of additional coast and inland 

 signal stations to aid in the daily forecasts. Tne Chamber also 

 pointed out in its petition that its members have, for a number of 

 years, printed bi-weekly weather reports, which were indispens- 

 able in the absence of a Government daily weather chart and 

 report. The Superintendent of the Meteorological Department of 

 the Government of India was sent to Bombay to make inquiries, 

 but his visit only resulted in the closing of the office in the 

 month of August. Since that time the head of the Telegraph 

 Department has superintended the forecasts. The scheme now 

 about to be tried is that, in consideration of a small monthly 

 payment by the Chamber of Commerce and the Port Trust, a 

 •daily telegraphic weather report chart and storm warnmgs and 

 a bi-weekly crop report will be supplied to each member of the 

 Chamber, 



Mr. R. Anurue has lately been collecting information as to 

 the use of signals by primitive peoples, and the facts he has 

 brought together— summarized in Science— are interesting and 

 •suggestive. American Indians use rising smoke to give signals 

 to distant friends. A small fire is started, and, as soon as it 

 burns fairly well, grass and leaves are heaped on the top of it. 

 Thus a large column of steam and smoke rises. By covering 

 the fire wiih a blanket, the Indians interrupt the rising of the 

 smoke at regular intervals, and the successive clouds are used 



for conveying messages. Recently, attention has been called to 

 the elaborate system of drim-signals used by the Cameroon 

 negroes, by means of which long messages are sent from village 

 to village. Explorations in the Congo basin have shown that 

 this system prevails throughout Central Africa. The Bakuba 

 use large wooden drums, on which different tones are produced 

 by two drum-sticks. Sometimes the natives " converse " in this 

 way for hours ; and, from the energy displayed by the drummers, 

 and the rapidity of the successive blows, it seemed that the co:i- 

 versation was very animated. The Galla south of Abyssinia 

 have drums stationed at certain points of the roads leading to 

 the neighbouring States. Special watchmen are appointed, who 

 have to beat the drum on the approach of enemies. Cecchi, 

 who observed this custom, designates it as a "system of tele- 

 graphs." The same use of drums is found in New Guinea. 

 From the rhythm and rapidity of the blows, the natives know 

 at once whether an attack, a death, or a festival is announced. 

 The same tribes use columns of smoke or (at night) fires to con- 

 vey messages to distant friends. The latter are also used in 

 Australia. Columns of smoke of different forms are used for 

 signals by the inhabitants of Cape York and the neighbouring 

 island. In Victoria, hollow trees are filled with fresh leaves, 

 which are lighted. The signals thus made are understood by 

 friends. In Eastern Australia, the movements of a traveller 

 were made known by columns of smoke, and so was the 

 discovery of a whale in Portland Bay. 



A VERY important series of vapour-density determinations have 

 been made by M. Alphonse Combes, which appear to decide 

 the much-discussed question of the valency of aluminium. It 

 will be remembered that a few months ago, as noticed in these 

 columns (vol. xxxviii. p. 624), Profs. Nilson and Pettersson, of 

 Stockholm, published the results of a most conclusive series of 

 experiments upon chromic chloride, showing that at the lowest 

 available temperature the density of the chloride corresponds so 

 closely to the formula CrClg, as to preclude the possibility of the 

 existence of molecules of CrjClg in the gaseous state. This 

 deci>ive result in the case of chromium, following; as it did after 

 the experiments of Prof. Victor Meyer and Dr. Griinewald upoa 

 ferric chloride, which also resulted in showing that the formula 

 FeClj represented the only stable molecular condition, appeared 

 to indicate that the metals of this group are really triads, and 

 that the double formula CuClg and Fe.jCig must be abandoned. 

 This conclusion was further strengthened by the fact that still 

 earlier determinations of the vapour-densities of the chlorides of 

 indium and gallium by Prof. Meyer, Prof-. Nilson and Petters- 

 son, and M. Friedel, had yielded conclusive results, pointing 

 to the formulas InClg and GaClj. In the case of aluminium, 

 however, the evidence has been by no means so decisive. As 

 shown by Dr. Young, in an admirable resume of all the experi- 

 mental data bearing upjn this question in Nature (vol. xxxix. 

 p. 198), determinations of the vapour-density of aluminium 

 chloride by Profs. Nilson and Pettersson showed that from 

 440"" C. the density gradually diminished, until at about 800" 

 it arrived at the value corresponding to AlClj, and then remained 

 constant fjr about 200', until, in fact, it began to break up with 

 liberation of free chlorine. On the other hand, Messrs. Friedel 

 and Crafts, in a beautifully graduated series of experiments, 

 found that at 218°, 31° above the boiling point, the density corre- 

 sponded almost exactly to the formula -A-UClg, and remained 

 practically constan' to 400'. More recently, Messrs. Roux and 

 Louise have found that, at temperatures near their boiling-points, 

 methide and ethide of aluminium jiossess densities corresponding 

 to the formulx' Alj(CH;,)„ and Al.jlCoH,,)^ ; these values, how- 

 ever, do not remain constant for any sufficient interval of temper- 

 ature, and so are by no means conclusive. At this interesting 

 moment M. Combes brings forward his experiments upon a new 

 compound, acetyl acetonate of aluminium, [AUC^H^Oj,),],, a 



