500 
NATORE 
[Marci 24, 1904 
ation of the pest. But we fear that it is too late now to 
do more than to oppose the insect by special methods of 
cultivation, and to institute stringent measures to try to 
prevent the invasion of districts not yet attacked. 
The weevii itself is a greyish beetle, very similar in shape 
to our own destructive apple weevil (Anthonomus pomorum, 
L.), which belongs to the same genus, but it is larger, 
measuring nearly a quarter of an inch in length. The eggs 
are laid singly in the ‘* squares’ or buds, which afterwards 
fall, or else in the ‘‘ bolls’’ or seed-pods, in one of which 
latter sometimes as many as twelve of the thick whitish 
grubs may be found. ‘They do not attack the leaves. 
The history of this insect is curiously like that of the 
Colorado potato beetle. In both cases insects previously 
only known to entomologists, and feeding in comparatively 
small numbers upon some wild plant (the original food-plant 
of the Boll-weevil has not yet been determined), have 
attacked a cultivated plant, and increased enormously with 
devastating effects, and spread over a large tract of country. 
One subject which demands immediate attention from 
Governments (apart from those of countries already in- 
fested) is the instant adoption of any precautionary 
measures which may be necessary to prevent the danger of 
from Texas or Mexico to other 
, such as Africa or India. 
W. F. 
the insect being carried 
cotton-growing countries 
Airey. 
GEOLOGICAL STUDIES IN PERU. 
HE third number of the Boletin del Cuerpo de Ingenieros 
de Minas del Peru (Lima, 1903), by Francisco Alayza y 
Paz-Soldan, director of the survey, raises several matters of 
general interest to geologists. It deals with the districts 
of Moquegua and Tacna, including some striking volcanic 
country between the Andes and the coast. The terrific 
eruption of Huainaputina in 1600 has left its traces in 
immense deposits of scoria across the adjacent country ; 
Fic. 1.—Ground disturbed by subsidence, Pallata. 
the crater of the mountain was completely blown away, and 
a barrier was formed by the ejected blocks, strong enough 
to convert the Tambo River for twenty-eight hours into a 
lake. Part of the devastation was due to the bursting of 
this barrier, and the phenomena of earthquake and ex- 
plosion justify the ranking of this catastrophe among the 
greatest in the human period. Since 1600 the voleano has 
become completely extinct. Its) northern neighbour, 
Ubinas, on the same line of activity, is, however, looked 
on with suspicion, and still emits vapours, accompanied by 
a continuous roaring. emanations have kaolinised 
the felspars in the surrounding lavas, and have formed 
alums, anhydrite, and sulphur near the vent. Though the 
fast eruption, about which little is recorded, took place in 
1662, it was of cataclysmic magnitude, and the author 
points out that repetitions may reasonably be expected. 
Disturbances of quite another nature are described from 
NO. 1795, VOL. 69 
hese 
Pallata, where sudden fractures of the volcanic surface have 
occurred as recently as 1902, leading to both depression and 
elevation. These are traceable to the absorption of water 
by the underlying tuffs, much as, according to Arcidiacono, 
the ‘‘ earthquake ”’ of Nicosia in 1901 was caused by the 
swelling up of clays during a rainy season, beneath a series 
of Miocene sandstones. The four excellent illustrations 
make us desire more from this little known region of Peru. 
It is unnecessary to emphasise the importance of the volcanic 
chain in connection with the Pacific coast-line, and with the 
suggestion, made by Rey y Bassadre, of a companion chain 
opening along some hidden fissure out at sea. 
Gi ANG: 
RELATION BETWEEN TEMPERATURE AND 
ELEVATION. 
]X a communication to the Comptes rendus of January last 
Prof. Teisserene de Bort gave a condensed account of 
the research relating to the decrease of temperature with 
elevation in the region of Paris. This investigation is, 
perhaps, the most complete that has been undertaken, for 
the deductions are made from the discussion of an excellent 
series of 581 aérial soundings by means of ballon- 
sonde extending over five years. From so many observ- 
ations the general conclusions are therefore of considerable 
weight, and the results of great importance. The author 
divides the observations into two groups, one (A) showing 
the results of 581 ascents, and the other (B) restricted to 
141 ascents when the altitude attained fourteen kilometres. 
In the tabular statements which accompany the paper the 
temperature values are given for every 500 metres up to 
a height of 5000 metres, ‘after which values for each kilo- 
metre rise are adopted ; the results are also grouped to show 
the changes between the four seasons of the year. Two 
sets of values for the air temperature in degrees Centi- 
grade are given here, namely, those obtained during 
summer and winter, the letters under each heading belong- 
ing to the groupings previously referred to :— 
Altitude Summer Winter 
A B A B 
Ground) seep chs 35) ..-0 0 QsO) eect eee 
500 m.... +13°9 ... +13°6 PM Pe (EY Corer ey RS SOs 
1,000 +118 ... +11°8 —- 04... — O'2 
T3500) =e -O°2 wats ON = 19 x. —sow 
2,000 ego's 2. ecg ee =) 327 ee I°4 
2,500 S"3 ss E570. a | US ea 
3,000 SEMI*7 ca, chy 200i sca) ee Ou2Eeny ON 
3,500 —10'4.... + O02 ... —TO:9 - $7 
4,000 <3 Aa (O27. ee SO. —10°9 
4,500 =e Se Syston TY] —14°2 
5,000 = 9°30. —2S'S) see 19755 -—17°0 
6,000 -1593 ... —14°8 = 26°45, 2307 
7,000) | s23 22°30 PTC ue : —31°5 
8,000... -~299 ... —29°3 — 39°0 
9,000 —379 ... —380 .. —46°9 
10,000 —45°2 —45°3 .. --54°0 
11,000 _- 5073) — —57°9 
12,000 — —527 . _ —57°9 
13,000 — = 5E5 = —56°9 
14,000 _— ety Meet ci, — —55°5 
The author refers in some detail to the peculiarities of the 
rate of decrease of the temperature, and indicates the “* zone 
isotherme ’’ previously noted by him, which lies at an 
altitude of about 11 kilometres, in which the temperature 
ceases to decrease, its altitude being the same for every 
month throughout the year. 
THE RELATION OF MATHEMATICS TO 
ENGINEERING.} 
WE may sum up what seem to be the best ideals in 
secondary school mathematics as follows :— 
These ideals come from the engineering professions. 
They insist upon quality rather than quantity. They insist 
that the problems shall be largely concrete and shall be 
worked out to an accurate numerical result. They insist 
1 Abridged from an address delivered by Prof. C. A. Waldo, as president 
of the section «f mechanical science and engineering of the American 
Association, at the St. Louis meeting. 
