x 
 Oct.9, 1873) 
NATURE 
497 
quantity of gas has to be heated than in the other case. It must, 
therefore, be heated up to a much higher temperature, and yet 
the spectrum is not continuous and the lines are not even 
widened. We are, therefore, compelled to accept Frankland 
and Lockyer’s original conclusion, that pressure and not heat is 
the cause of the widening of the lines. 
The question is one of considerable importance. If tempera- 
ture would widen the lines, the widening ought always to begin at 
the same temperature, and the hydrogen in the solar protuber- 
ances which show only narrow lines could not be at a higher 
temperature than the hydrogen in our vacuum tubes, the moment 
the lines begin to widen. If our conclusion, however, is cor- 
rect the breadth of the lines will give us no indication whatever 
as to the temperature of the gas. . 
Dynamometers, by R. S. Ball, LL.D., F.R.S. 
If we adopt that force which acting on one gramme for one 
second will impart the velocity of one centimetre per second as 
the unit, then one million of such units is a convenient magni- 
tude for practical purposes. The large figures on the dyna- 
mometers represent these million units, for which it is hoped that 
ere long a suitable name will be adopted. The dynamometers 
are intended for educational purposes. They are exhibited to 
the Association with the desire of aiding the present movement 
in favour of an improved system of fundamental unity. 
SECTION C.—GEOLoGY 
Concluding Report on the Maltese Fossil Elephants, by Dr. A. 
Leith Adams, F.R.S. - 
For thirteen years Dr. Leith Adams has prosecuted his re- 
searches upon the fossil elephants of Malta, and he now presented 
the final report upon this subject. Three forms of fossil elephants 
occur here which are unknown elsewhere, all of small size. The 
largest is the Zlephas Munaidriensis (L. Adams), which attained a 
height of seven feet. In the crown sculpturing of the molars 
this species resembles Zilefhas antiquus; as regards the 
ridge-formula, its nearest ally is Loxodon meridionalis. Llephas 
Melitensis (Falconer and Burk) varied in size ; its average height 
was about five feet ; this too belonged to the Loxodon group. 
The smallest bones known to the author belonged to an ele- 
phant only three feet high, called Zvephas Falconeri, by Busk. 
Although there appears to be some evidence for separating 
this from the other forms, yet the author stated that 
“there is no difficulty in arranging a graduating series of 
specimens from the smallest up to the largest bones ascribable to 
the Zilephas Melitensis.” 
The elephants all occur in the same deposit, and with them 
there are remains of Hippopotamus Pentlandi and H. minutus. 
There is also a gigantic dormouse and a large extinct swan, 
besides some reptilian remains not yet fully worked out. 
The report concludes as follows :—‘‘It must be apparent that 
this (for the most part) unique fossil fauna restricted to a small 
mid-ocean island, presents several interesting contrasts with 
reference to the Mammalia in general, and elephants in par- 
ticular,.which frequented Europe during late geological epochs. 
For example, between Rome and Sicily we find remains of the 
Elephas primigenius, Elephas antiguus, and Elephas meridionalis. 
In the caves of Sicily, traces of the African elephant have been 
discovered, and also molars, barely distinguishable from those of 
the Asiatic species, and which, under the name of Zi/ephas Ar- 
meniacus, are traceable eastward into Asia Minor, in the direc- 
tion of the present habitat of the living species. It looks, 
indeed, as if the eastern basin of the Mediterranean had been at 
one time a common ground where all these extinct and living 
elephants met, and from whence, with other animals, they have 
disappeared or been repelled to distant regions.” 
Sub‘ Wealden Exploration.—1. General Report, by Henry 
Willett. 
In this report Mr. Willett gave a summary of the results 
achieved up to the present time, the details having already been 
published in his quarterly reports. 
The boring was commenced at the time of the last meeting of 
the British Association at Brighton, and its object is to explore 
the rocks underlying the Weald of Sussex. A bore of 63 
inches diameter was at first adopted, but at the urgent recom- 
mendation_of Mr. Prestwich, one of g-inch diameter was em- 
ployed. The bore has now reached a depth of 300 feet, and 
the engineer (Mr. Bosworth) has contracted to increase it to a 
depth of 418 feet at the cost of only 1/. per foot. Of the 300 
feet of strata already passed through, about 70 were previously 
known, but the remaining 230 are new to science ;+50 feet of 
this consists of valuable beds of gypsum. 
Mr. Willett has designed a novel form of drill which possesses 
the following advantages :—(1) It cuts only the circumference ; 
(2) it makes better progress ; (3) the central core is Jeft intact ; 
(4) the tool not unfrequently extracts the core itself. The gyp- 
sum was extracted by this means, and it is believed that no such 
cores have been brought to the surface from similar depths in 
this country. 
Sub-Wealden Exploration.—2. 
Topley, F.G.S. 
The author commenced by repeating the protest, often made 
already, that the Sub-Wealden Exploration was not a “search 
for coal.” It is simply an endeavour to explore the rocks which 
underlie the Weald and especially to reach the Palzeozoic rocks. 
Whatever these rocks may prove to be, if reached at all, the 
boring will have succeeded. The results of this boring cannot 
fail to have important bearings upon the question of the probable 
occurrence of coal measures beneath the South-East of England, 
but the discovery of coal is not the object in view. 
An account was then given of the lowest beds exposed at the 
surface in Sussex, and of the reasons which have led many 
geologists to consider them as representatives of the Purbeck 
Beds. The thickness of Purbeck Beds previously known in 
Sussex was somewhat over 300 feet ; probably about 230 addi- 
tional feet of strata have been made known by the boring, in 
which there are some valuable beds of gypsum. 
The boring commences about 250 down in the known Purbeck 
Beds ; up to Sept. 1 it had reached a depth from the surface of 
294 feet. It is not safe at present to speculate upon the geologi- 
cal age of the lowest beds reached in our boring, but additional 
evidence will probably soon be obtained.* 
The author then pointed out that most of the bore holes 
which have been put down to the Palzeozoic rock through newer 
strata have reached those older rocks at about 1,000 feet below 
the sea. There is a probability then that at or about this depth 
the palzeozoic rocks will occur beneath the Weald. These places, 
however, are on, or to the north of, the westerly prolongation of 
the Axis of Artois, whilst the boring is to the south of that line ; 
it is therefore possible that different conditions may prevail 
here, 
Attention was then drawn to the fact, already pointed out by 
Mr. Godwin-Austen, that the dip of the carboniferous limestone 
in the Boulonnais is to the south, whilst in the Pays de Bray 
the same limestone has been found at a depth of 57 feet from the 
surface, underlying Kimmeridge clay. It is then probable that 
under the secondary rocks near to the south of Boulogne there is a 
basin of palzeozoic rocks, in which the coal measures may be pre- 
served ; this basin might possibly be prolonged to the west be- 
low the Wealden district of the south-east of England. 
In the course of the discussion which followed the reading of 
these reports, Sir John Hawkshaw stated that many people, 
himself included, took an interest in this question chiefly from 
the hope that coal might be found ; but even if in this respect 
we were doomed to disappointment it would still be of great 
importance to show that, at that particular spot, no coal existed. 
Prof. Phillips thought that the object sought was neither coal, 
gypsum, nor salt ; but that something exists below the Wealden 
is certain, and that something we are now searching for. A dis- 
cussion then took place as to the best mode of conducting deep 
borings. Mr. R. Russell, C.E., spoke of the great value of the 
diamond boring process; but from remarks made by other 
speakers it appeared that, although the diamond is admirably 
adapted for boring small holes in hard rocks, it is not so well 
suited for conducting such an operation as that under discussion. 
On the Arenig and Llandeilo Rocks of St. David’s,by Henry 
Hicks, F.G.S. 
The object of this paper was to follow out the succession of 
the rocks in the neighbourhood of St. David’s, commenced in 
previous papers communicated to the British Association. The 
section was now completed to the top of the Llandeilo series, 
The Arenig and Llandeilo groups were each divided into an 
upper and a lower series, the author believing that in each case 
Geological Report, by W. 
* Since this Report was read, Prof. Phillips has broken up and carefully 
examined parts of the cores brought up from the bottom of the boring ; in 
a he a found Linguda ovalis, which occurs in the Kimmeridge Clay. 
ee p. 457. ; ; 
