Oct. 15, 1885 | 
NATURE 
573 
cylinders for the usual knives was also tried, and every 
care taken to prevent the inclusion of dust, but the results 
were very unsatisfactory. 
The results obtained are as follows :— 
Length of second’s pendulum reduced to sea-level at the 
equator. 
Metre. 
Alleghany Observatory eid 09909384. 
Bbensburge ses) so cen bss oes 0°9910672 
Morks ees cs *s: O'QQIOIS 
At Alleghany, the effect of a valley was not taken into 
account, as there was no topographical survey available ; 
the necessary correction will slightly increase the above 
value. 
LETTERS TO THE EDITOR 
[The Editor does not hold himself responsible for opinions expressed 
by his correspondents. Neither can he undertake to return, 
or to correspond with the writers of, rejected manuscripts. 
No notice ts taken of anonymous communications. 
[The Editor urgently requests correspondents to keep their letters 
as short as possible. The pressure on his space ts so great 
that it is impossible otherwise to insure the appearance even 
of communications containing interesting and novel facts.| 
The Presence of the Remains of Dicynodon in the 
Triassic Sandstone of Elgin 
In my address to the Geological Section of the British Asso- 
ciation I was fortunately able to announce a discovery which is 
of the very greatest interest both to geologists and biologists. 
As this discovery was made only a few days before the com- 
mencement of the meeting at Aberdeen, and after the draft of 
the address was in type, it does not appear in your columns; I 
will therefore ask you to insert this note upon the subject. 
Visiting the ‘‘Cutties Hillock” quarry near Elgin early in 
September, I found that the workmen had recently obtained a 
new specimen of a reptile, in which the head was preserved. On 
examining this I found that there were clear indications of two 
large canine teeth in the upper jaw with permanent pulp cavities. 
These characters and the general form of the skull left scarcely 
the smallest doubt in my mind that the remains must belong to a 
reptile closely allied to Dicyzodon. From the examination of a 
photograph which I submitted to him, my friend Dr. Traquair 
was able to fully confirm this conclusion, and to lay a pre- 
liminary note on the specimen before the Geological Section at 
Aberdeen. I hope that ere long he will be able to give a com- 
plete description of it. 
As Dicynodonts have hitherto been only found in South 
Africa, in India, and in the Ural Mountains, this discovery is 
an exceedingly important one. Seeing that doubts have been 
expressed concerning the Triassic age of the South African 
deposits, the occurrence of the very characteristic African form 
in the Trias of Western Europe is an important link in the chain 
of evidence by which these beds have been correlated. It is 
interesting, too, to be able to point out that the sandstones of 
Elgin, concerning the age of which such a great amount of 
controversy has taken place, have now yielded reptiles belonging 
to no less than four orders—namely, the Lacertilia, the Croco- 
dilia, the Dinosauria, and the Dicynodontia. J. W. Jupp 
An Earthquake Invention 
WHILE on a visit to the Melbourne Observatory I saw 
NATuRE of July 2 containing two letters from Prof. Piazzi 
Smyth, intended to expose a piratical attempt on the part of a 
“* B.A, man” to adopt an idea of Mr. David Stevenson with 
regard to the construction of houses to withstand earthquake 
motion. The publication of the first of these letters is at the 
request of Mr. D. A. Stevenson. The piracy referred to by 
Prof. Smyth is a brief note in a paper written by myself. My 
name is at the head of it (see Refort to the B.A. 1814). Prof. 
Smyth complains that I have not taken notice of a paper written 
some twenty years ago by Mr. D. Stevenson. I regret to say that I 
am not acquainted with that paper, and how Prof. Smyth expects 
that I should be when living 10,009 miles away from collections 
of European books, I fail to see. I am, however, acquainted 
with very much relating to aseismic or aseismatic tables, and if I 
made reference to the work of Mr. David Stevenson, I must 
necessarily have referred to the work of others. As every 
report which I have hitherto written for the British Association 
has been in the form of notes which have subsequently been 
expanded in special papers, an historical account of aseismic tables 
would have been out of place. Prof. Smyth is apparently only 
acquainted with the work of Mr. D, Stevenson. Under the 
head of aseismic tables I include ball and plate seismographs, 
the lamp tables in certain Japanese lighthouses, two model 
houses which I constructed in Japan, together with the model 
lighthouse spoken of by Prof. Smyth, and my own dwelling 
house. dl of these involve the same principles, and they only 
differ in their dimensions. 
(1) Ball and Plate Seismographs.— Of these seismographs I 
have constructed several types. At the time of an earthquake, 
in consequence of acquiring a surging movement, they fail to 
give reliable records. ‘They have been independently invented 
and described as original by many. Mr. Briggs, of Launceston, 
Tasmania; Dr. Verbeck, of Tokio, Japan; Mr. T. Gray, of 
Glasgow ; Mr. D. A. Stevenson, of Edinburgh, &c., have all been 
authors of such instruments. 
Mr. D. A. Stevenson recently figured and described his form 
of seismograph in the pages of NaTuURE. If we overlook certain 
mechanical defects in this instrument, as, for instance, attaching 
a recording index to the edge of the ‘‘steady plate” rather than 
at its centre ofinertia, the resemblance of Mr. Stevenson’s con- 
trivance is strikingly like a seismograph the photographs and 
descriptions of which existed in several societies and libraries in 
Britain prior to the appearance of Mr. Stevenson’s invention. 
After reading Mr. Stevenson’s description I did not ask for the 
publication of an ‘‘interesting”’ and ‘‘ well-put” letter, accus- 
ing Mr. Stevenson of having appropriated the ideas of others, 
but I furnished him with copies and references to papers in the 
Transactions of the Seismological Society and other periodicals 
where mention was made of this type of instrument. 
(2) Lamp Tables.—As 1 have been an officer in the Public 
Works Department of Japan for the last ten years, where I have 
every facility of knowing what the performance of the lamp 
tables at the lighthouses has been at the time of severe earth- 
quakes, I trust that some credence may be given to what I may 
say on this subject. When I last made inquiries about these 
tables, I found that they were all regarded as failures and one 
and all had been clamped. If Mr. Stevenson would like to 
have details respecting these failures I shall, on my return to 
Japan, have great pleasure in making them public. 
Mr. Mallet, in his “ Palmieri’s Vesuvius,” very distinctly 
states that he was consulted by Mr. Stevenson respecting the 
Sapanese structures, and that the principles indicated hy him 
(Mallet) were followed out in their construction. 
As Mr. Mallet is dead, perhaps Mr. Stevenson or Prof. 
Smyth will kindly enlighten us as to the meaning of this 
passage. Although I have made seismology a speciality for 
some years, I must confess that I am as yet in the dark as to 
who was the first inventor of the aseismic joint. To me it 
appears that there have been many inventors. 
(3) Jodels.:—My first model was about as large as a good- 
sized dog kennel. For a short-period oscillatory movement the 
house resting on its rollers remained at rest. Prof. Smyth 
speaks of Mr. Stevenson having imitated earthquake moti»n by 
the blows of a sledge-hammer. Although Prof. Smyth regards 
the blows of a sledge-hammer as an admirable illustration of 
earthquake motion, any one acquainted with the true nature of 
earthquake motion would decline to recognise Mr. Stevenson’s 
test as any test whatever. 
(4) Butlding.—The only duzlding placed on free foundations 
with which I am acquainted is the one I have erected in Tokio. 
At first it rested on balls, and, like Mr. Stevenson’s lamp tables, 
it was for certain reasons a failure. Now it rests on spherical 
grains of cast-iron sand. It is now astatic, and I regard it asa 
success. At the time of an earthquake the motion outside the 
house is usually about six times what it is inside. A description 
of it will be found in the Resorts of the British Association for 
1885. 
ae what I have now said it will be clear that I have no 
desire to claim the authorship of the aseismatic joint. Detailed 
reference to the obscure and manifold authorship of what has 
hitherto proved a failure would certainly have been out of place 
in the report to which Prof. Smyth has referred. 
Had Messrs, Stevenson and Smyth been acquainted with the 
nature of earthquake motion, a few of the more important facts 
in the history of the ball and plate joint, and the details of the 
