NA TURE 



\_Feb. lo, 1 88 1 



Another slight shock of earthquake was felt at Berne on the 

 uight of the 1st inst. Fresh earthquake shocks are reported from 

 Agram, \\here shocks were observed on January 25 at ih. 15m. 

 (in the morning) iih. a.m. ; on the night of January 26 at llh. 

 28m. ; in the morning of January 3 1 at 3h. ; on January 3 at 3h. 

 (in the morning), ih. 15m., and 4h. 13m. p.m. la the uight of 

 January 27-2S shocks were felt at St. Ivan, Zelina (Hungary) at 

 I2h. 52m., 3h. 9'ai., 4h. 32m. On January 28 two shocks were 

 felt at Gurkfeld (Carinthia) and neighbourhood at 8h. Som. 

 p.m., direction north-west to south-east. Earthquakes were 

 also noticed on January 25 at Venice, Bologna, and Padua. 

 In the night of January 3-4 shocks w ere observed in the regions 

 of the Carinthian Alps, in Klagenfurt, at 2h. 22 ja. 25s., direction 

 east to west, duration 5-65. ; in Trieste at 2h. 24m., direction 

 north-east to south-west, duration about 4s. ; at the same time 

 shocks were felt in Laibach, in Gurkfeld, and in Czegled 

 (Hungary). 



AN examination has taken place at Brussels of the railway 

 employh, in order to test their eyes. More than one-twentieth 

 of them have been found defective, and consequently will be 

 discharged as being unable to fulfil their functions with a sufficient 

 security for travellers. 



THE AURORA AND ELECTRIC STORM OF 

 JANUARY 31 



AXrE have received the following further communica- 

 '^' tions on the recent brilliant display of aurora: — •^ 



The beautiful display of aurora on the evening 

 of Thursday was accompanied by the usual earth-cur- 

 rent disturbances. They were evident o/er the whole 

 of the United Kingdom. Telegraphic lines were stopped, 

 railway block-signals were disturbed, and all the usual 

 accompaniments of these curious storms were observed. 



The electric storm commenced about 3 p.m., it reached 

 a maximum at 6.40 p.m., and disappeared about 9 p.m. 

 It was renewed about 11 p.m., and disappeared again 

 about I a.m. on the next morning. The currents attained 

 an intensity that I have never before observed. At Llan- 

 fair in Anglesey they measured 41 '4 millivebers. At 

 Haverfordwest 30 millivebers; at Bristol I7'32 milli- 

 vebers ; in the Central Station, London, 11 milli- 

 vebers ; at Edinburgh 8 millivebers. Now as working- 

 currents vary from 5 to 10 millivebers, it is clear that 

 these uninvited wanderers must play sad havoc with the 

 working telegraphs. In some instances they were strong 

 enough to ring the bells used on railways. They are 

 eliminated, where this can be done, by joining two wires 

 in metallic circuit, and so e.\cludmg the earth. They were 

 characterised by the usual reversals, the direction of the 

 current changing slowly. The changes in direction and 

 variation in strength were always observed on the southern 

 lines first. The line of maximum force commenced south- 

 east to north-west, then passed south to north, and ended 

 south-west to north-east. 



It is unfortunate that on such occisions the whole 

 energies of the technical staff are taken up in maintaining 

 communication, and that no time or means can be found 

 to obtain accurate measurements. The results however, 

 such as they were, fully confirm my view that these storms 

 are due to a violent disturbance of the distribution of 

 electric potential on the earth's surface arising from 

 violent changes in the electrification of the sun. There 

 ■was a violent disturbance in the sun's envelope on that 

 day, as I learn from Mr. Norman Lockyer, and I am 

 looking with interest to some particulars of it. 



February 5 W. H. PreeCE 



On yesterday evening-, January 31, a most brilliant display of 

 the aurora was seen here. It was by (ar the finest I hive seen. 



and others have expressed the same opinion. At 6.25 p.m. I 

 saw a considerable illumination on the northern horizon, and an 

 outlying bright patch on the north -w-est having somewhat the 

 appearance of the zodiacal light, as shown in the .sketch. Fig. i. 

 This outlying patch was distinctly in motion along the horizon 

 towards the west; streamers from the horizon then shot up, and 

 there appeared several arches of light apparently about the 

 width of an ordinary rainbow, passing from the north-west to 

 north-east points on the horizon ; these arches gradually ap- 

 proached the zenith, and the southernmost fro.n the ean and west 

 points of the horizon at last passed through it. Some of these 

 arches are shown in Fig. 2, but there were more visible. In a 

 feu minutes, about 6.40, the arches faded, and there appeared, 

 rather west of north, a mass of bright green light ; then the 



sireaniers from !the north lengthened out, as shown in Fig. 3, 

 converging on the Pleiades, as near as I could judge ; waves of 

 red light cimmenced to pass upwards along them, and large 

 sheets of light appeared to pass rapidly over the sky. The 

 streamers gradually died away, leaving flashing lights near the 

 horizon, which in their turn left a slight light over the northern 

 horizon, which gradually faded auay. Mr. Percy Smith made 

 the sketches, but owing to the rapid changes their accuracy Is 

 only general. Both he and I saw only one line in the spectrum 

 in the usual place. George M. Se.4.broke 



Temple Observatory, Rugby, February i 



The aurora observed during the evening of January 31 was 

 accompanied by a magnetic perturbation, and although it was 

 on a much smaller scale than that registered on August 12 to 14 

 last, a brief account of it may possess some slight interest to your 

 readers. 



The magnets of all three instruments at Kew, the declination, 

 bifilar, and balance magnetomers, began to be disturbed to a 

 somewhat larger extent than usual about noon on the 31st, the 



