gi2 
plants on plants, animals on animals, and one on the other ; the 
fertilisation of plants by insects, and the attractability of diff2- 
rent colours for diffzrent insects. Other points recommended 
for study were the following:—The manner in which the 
habits of animals have been acquired ; the manner in which 
varieties or species have been formed ; the limit of the succes- 
sive genera‘ion of insects through none but females ; the diseases 
of plants due to parasitic fungi and insects. 
Tue first number of Petermann’s AMittheilungen contains a 
b.ief account of the eruption of a new volcano in Chili, which 
occurred during part of last Jume and July. The volcano, 
known by the name of Lhagnell, is situated in the south of the 
country, in Arauco, between the volcanoes Villarico and Llaima, 
near the river Cautin. Immense quantities of sand seem to have 
been thrown out, some of which, according to Dr. Philippi, of 
Santiago, reached a distance of 300 or 400 miles north from the 
volcano. This sand is described as consisting of angular, tran- 
Sparent greea particles of volcanic glass. Dr. Philippi also 
Teports that for fourteen days, about midday, a stronz south 
wind blew, as far north as Santiago, small quantities of sand, 
much coarser than the above, with rounded corners, opaque and 
grey. Great quantitics of lava, according to the report of a 
spectator, have overflowed the district, causing considerable 
destruction to life, and stopping up the river Quepe, which is 
thus being converted into a considerable lake. 
We have received a small pamphlet, by Mr.-B. H. Babbage, 
coataining a description of a portion of the late Mr. C. Babbage’s 
calculating machine or difference engine, put together in 1833, 
and now being exhibited in the educational division of the South 
Kensington Museum. 
La Revue Scientifique for February 15, gives a summary of the 
mu-h needed administrative reforms which have been introduced 
into the Collége de France. - 
WE have received the following papers recently read before 
the Eastbou-ne Natural History Society:—‘‘On Geoglossum 
difforme or Earth-tongue,” by Mr. C, J. Muller; ‘‘A Note on 
the Wall Pelletory,” by Mr. F.C. S. Roper; ‘‘On the Planet 
Venus,” by Mr. T. Ryle. 
THE principal articles in the Quarterly Fournal of Science 
are :—‘* On the Probability of Error in Exper:mental Research,” 
by Mr. Crookes ; ‘‘ Condition of the Moon’s surface,” by Mr. 
Rk, A. Proctor, with photograph ; “Colours and their Relations,” 
by Mr. Mungo Ponton ; and ‘‘ Remarks on the Present State of 
the Devonian Question,” by Mr. H. B. Woodward. 
THE Annual of the Royal School of Naval Architecture, &c., 
contains some good technical papers. This publication will be- 
cone vastly increased in importance, and we hope in value, by 
the establishment of the new school at Greenwich. 
WE take the following from the Zxgincer :—The question as 
t> whether a gasometer will explode when fired was settled in 
Manchester on Tuesday, February 11, when one of the gas- 
meters at the Manchester Corporation Gasworks in Rochdale- | 
road was destroyed by fire. The origin of the fire is not known, 
but about 2 o’clock a workman saw flames issuing from one end 
of the gasometers, and the flames could not be checked till the 
whole contents of the gasometer, about 600,000 cubic feet of 
gas, had been consumed. Many inhabitants of the neighbour- 
hood hurried away with loads of their furniture, fearing an ex- 
plosion, but nothing of the kind occurred. 
ADVICES from Cyprus state that no rain had fallen on the | 
island for months ; but this is probably an exaggeration. 
WE learn from the A¢heneum that the Rev. Thomas Hincks, 
F.R.S., is now engaged in preparing a ‘‘ History of the British 
Polyzoa.” 
NATURE 
[ Feb. 20, 1873 _ 
PROFESSOR RAMSAY ON LAKES 
ROF. RAMSAY, F.R.S., delivered a course of six lectures 
to working men, on Monday evenings, commencing Jan. 5, 
1873, in the Lecture Theatre of the Geological Museum. The 
subject of the course was ‘‘ Lakes, fresh and salt: their origin, 
and distribution in geographical space and in geological time,” 
and the following is an abstract of them :— 
I, FRESHWATER LAKES, THEIR ORIGIN AND GEOGRAPHICAL 
DISTRIBUTION 
There are many classes of lakes in the world, formed ia 
various ways, and though he had been unjustly charged with | 
ascribing all lakes to one origin, he would be the last person to 
doso. He then went on to examine the various means which 
might be supposed to produce lake basins, and especially that 
class of lakes scattered over the whole northern hemisphére—in 
Wales, Cumberland, Scotland, Sweden and Norway, Russia. 
and N. America—the basins of which had evidently been formed 
by the erosion and grinding out of portioas of the earth’s crust. 
In many cas2s these lakes are in true rock basins, surrounded by 
lips of rock. How were these hollows produced by Nature ? 
The dislocations of the earth’s crust could not produce them ; as 
a rule the sides of faults are close together or the fissure is filled 
up with other matter, and the depressions due to synclinal 
curves were never so simple or perfect as these lake basins, 
owing to violent disturbances, and to subsequent denudation. 
The theory of a special area of subsidence for each lake seems 
absurd, on considering the vast numbers of separate lakes, in 
N. America for example, lying in some case within a mile or 
two of each other. Again, a lake cannot make its own hollow ; 
what little motion there is in the water can only affect the waste 
of the shores. Neither can a river scoop out a lake hollow, it 
can only produce a long narrow channel, and go on widening 
and deepening that, and the sediment which it carries down ~ 
into the lake will in the long run fill up the lake basin. The 
action of the sea, too, on its shores cannot scoop out a lake 
hollow, it can merely wear back its cliffs and forma ‘‘ plain of 
marine denudation” just below the level of its waters. And 
thus having exhausted all the other natural agencies which effect 
the denudation of the land, what agency remains to us to account 
for the formations of these lake basins, but the grinding power 
of ice? The lecturer then adverted to the phenomena of the for- 
mition and progress of glaciers, illustrating his remarks by 
diagrams of the great Rhone glacier. In the Alpine valleys 
there are numerous iadications—in the mammellated surface of 
the rocks, the striation, moraines, and boulders—that at some 
period in the past all these glaciers had been very much more 
extensive than at present, and were found in many parts where 
now they are altogether wanting. In G:eenland the whole 
country is covered by a universal ice sheet, which extends into 
the sea in some cases several miles, and where cliffs of ice ris> 
out of the sea 209 to 300 ft. high, and, as recent soundings have 
shown, are sometimes 3,000 ft. deep. Large masses of these 
breaking off float away as icebergs, bearing with them stones and 
rubbish which they deposit, on melting, irregularly over the 
sea bottom. Inthe mountains of Wales and Scotland, in the 
Vosges, the Black Forest range, and in N. America are nume- 
rous signs of glacier action, all which prove that at one period, 
recent in a geological sense, glacier; were present in those dis- 
tricts ; and boulders and boulder clay deposits show also that 
the Northern part of the Northern hemisphere was passing 
through a glacial epoch. 
Boulder clay and moraines have sometimes dammed up a 
stream of water aud formed a lake, but lakes of that kind are 
neither numerous nor of much importance. The theory that the 
true rock basins were scooped out by glaciers first occurred to 
the lecturer whilst observing in N. Wales, and he applied it 
first to the eXplanation of the tarns about SnowJon, but ex- 
tended observation of the Italiaa and other great lakes, and 
subsequently of the American lakes, warranted him in applying 
it to them also. He had e-pecially applied it to the Lake of 
Geneva, which lies directly in the course of the old Rhone 
glacier. The lake is 983 ft. in depth in its deepest part, nearly 
in the centre. Where the glacier entered the lake it could not 
have been less than 3,009 fr. thick, and as the rock underneath 
is comparatively of a soft character, where the ice was thickest 
the grinding power was greatest, and it scooped out its deepest 
hollow ; but towards the south end the mas; had grown less 
through melting, and the result was a shallowing of the basin 
It is in the valleys of Sw tz2rlanl down which the glaciers must 
