JUNE 17, 1915] 
NATURE 
439 

iron sandwiched with ternary eutectic and then 
forging down to a j-in. sheet. This treatment 
squeezed out the excess of eutectic and left the juxta- 
posed faces perfectly united with a thin layer rich in 
phosphorus. After very slow cooling, sections were 
cut, polished, and etched. The structure was found 
to consist of ‘‘ strings of disconnected patches of pearlite 
and straight lines of ferrite,” very similar to those 
found in ship and boiler plates. All the carbon 
originally present in the eutectic was found to have 
diffused into the iron beyond the phosphoretic junc- 
tions. Heating to 1350° C., however, followed by a 
three days’ cooling period to 700° C., caused a uniform 
distribution of the carbon and phosphorus in the 
steel. 
Dr. Stead’s general conclusion is: ‘After careful 
study I am inclined to believe that if they ’’—1.e. ghost 
lines—‘‘ are not associated with a material amount of 
slag inclusions, they are not dangerous or liable to 
lead to the failure of engineering structures. I am 
led to that conclusion by submitting cross-sections to 
violent shock test, so that the stress applied is greater 
across the lines; for when this is done fracture does 
not start where they are located unless there are 
sulphide or slag inclusions in material quantity. The 
subject should have more consideration, and be 
thoroughly investigated by making suitable mechanical 
tests.” 
Only two aspects of Dr. Stead’s publication have 
been touched upon in this article. The complete 
paper, however, should be studied by those who are 
interested in the presentation of the subject in a 
series of masterly and informing sub-papers which no 
one but he could have written. 
H. C. H. Carpenter. 

THE SEISMOLOGICAL SOCIETY OF 
AMERICA. 
[Rows volumes of the Bulletin of this society were 
completed with the last year. They contain 
many papers of interest and value, most of which 
have been noticed in these columns, and _ several 
—evidently the work of novices—which the Pub- 
lication Committee might with advantage have 
suppressed. 
The first part of the fifth volume, which has been 
issued recently, contains six papers, three of which 
are of general interest. Of the others, one on the 
seasonal periodicity of earthquakes is inconclusive. 
Mr. Carl H. Beal describes an éarthquake which 
originated near the town of Los Alamos, in south- 
western California, on January 11 last. This is prob- 
ably the first earthquake in which the long-distance 
telephone has been used in the collection of records. 
Prof. J. C. Branner insists on the untrustworthiness 
of personal impressions on the direction of an earth- 
quake-shock, and he urges that, in investigations of 
an earthquake, the question dealing with such im- 
pressions should be omitted. It has long been known 
that single observations on the apparent direction of 
the shock or on the fall of a column, etc., are value- 
less, the apparent direction being almost invariably 
perpendicular to the principal walls of the house in 
which it is observed. But the average of a large 
number of personal observations within a limited area 
has been found in several cases to coincide with the 
direction of the area from the epicentre. Moreover, 
after the Tokyo earthquake of June 20, 1894, Prof. 
Omori measured the direction of fall of 140 stone 
lanterns with circular bases in Tokyo, and the average 
of these measurements coincides exactly with the direc- 
tion of the single great oscillation registered in that 
city. 
NO. 2381, VOL. 95| 


The first place in the number is given to Mr. Carl 
H. Beal’s account of the Avezzano earthquake of 
January 13. The material of this paper is derived 
chiefly from newspaper reports and from a_ short 
article which appeared in Narure (vol. xciv., p. 565), 
but the author adds an interesting note with regard 
to the origin of the earthquake. ‘‘ The higher moun- 
tain ranges near Avezzano,’’ he says, “rise to an 
altitude of from 6000 to 7ooo ft. and trend generally 
north-west and south-east, the direction apparently 
being determined by a series of nearly parallel frac 
tures which extends from a region south-east of Avez 
zano north-west to the vicinity of Cittaducale. . . 
A fault is known to pass through Luco, Cappelle, 
Sourcola, and very close to Avezzano, and as these 
cities were completely demolished, it is quite probable 
that movement along this fracture caused the shoclx.”’ 
On November 8, 1914, a fairly strong earthquake 
was felt in central California. From the duration of 
the preliminary tremors at Berkeley, and from the 
initial times at Santa Clara and the Lick Observatory, 
and taking the velocity for the tremors at Zeissig’s 
value of 6-3 km. per sec., Mr. E. F. Davis finds that 
the epicentre was situated on the San Andreas Rift, 
close to the town of Laurel. From a study of the 
distribution of intensity, Mr. Carl H. Beal had pre- 
viously assigned approximately the same position for 
the epicentre. The San Andreas Rift is the great 
fault along which for 270 miles the movements took 
place which gave rise to the Californian earthquake 
of 1906. 
Since 1832, there have, according to Mr. H. O. 
Wood, been twenty-five eruptions of Mauna Loa, in 
the south of Hawaii. With the majority of these no 
earthquakes are recorded, and this might also have 
been said of the last eruption which began on Novem- 
ber 25, 1914, had it not been for the instrumental 
record of a large number of feeble shocks. Mr. Wood 
concludes that “nothing appears in the sequence of 
events which would have justified confident, or definite, 
prediction of outbreak,” though the numbers of shocks 
recorded during the five preceding weeks were one, 
five, sixteen, thirteen, and thirty-eight. 
C. Davison. 
INDIAN GEODESY.} 
ee two volumes referred to below supplement one 
another, for while the general report gives an 
abbreviated account of the year’s work, more detailed 
descriptions and the discussions of the results obtained 
find their place in the Records. 
Pendulum observations were made at fourteen 
stations between lat. 20° N. and lat.- 30° N., 
all in the immediate neighbourhood of the 78th meri- 
dian, thus filling in the gap which existed between 
Lieut.-Colonel Lenox-Conyngham’s work from Mus- 
soorie to Meerut, and that of Captain Cowie in the 
Central Provinces. The stations include that of 
Kalianpur, the station of origin of the Indian tri- 
angulation, and here the pendulums were swung in 
the same room where Captain Basevi swung his 
pendulums in 1867. At Dehra Dun the new pendulum 
room was used. Some changes have been introduced 
in presentation of the results; Helmert’s formula of 
tgo1 is employed instead of that of 1884, which had 
been used previously; also the formula for the mass 
correction has been modified by taking somewhat 
smaller values for the mean surface density of the 
1 “*General Report on the Operations of the Survey of India during the 
Year 1912-13.”. By Colonel S. G. Burrard, C.S.1., R.E., F.R.S. (Calcutta, 
I¢T4. “ 
‘Records of the Survey of India.” 
1912-13. (Calcutta, 1914.) 
Vol. v., Reports of Survey Parties, 
