j 
FEBRUARY 5, 1914| 
The Eugenics Education Society. 
In Nature of January 29 there is a letter from 
Prof. Karl Pearson pointing out that he has been 
misquoted in The Eugenics Review, the word “years” 
having been substituted for the words “few months.” 
An apology to Prof. Pearson for this purely acci- 
dental blunder will appear in the next issue of the 
review. I should be glad if you would give me space 
to say through your columns also that we much regret 
that this mistake was made. 
LeonarD Darwin. 
(President.) 
The Eugenics Education Society, Kingsway House, 
Kingsway, W.C., January 31. 
OBSERVATIONS AT THE BOTTOM OF 
THE CRATER OF VESUVIUS. 
i: Waxoas the appearance of the interesting 
“7 memoirs of M. A. Brun, of Geneva, and 
the publication of his important monograph, no 
NATURE 
633 
are quite subordinate to the water-gas—is an 
erroneous one; he, on the other hand, main- 
| tains that his observations prove (alike in the 
blasts of vapour from volcanic vents, in the 
distension of molten lava into pumice, and its 
dispersion as dust) that water plays but an in- 
significant part as compared with other gases. 
The discovery by Prof. Malladra of a prac- 
ticable route by which the very lowest point in 
the present Vesuvian crater can be reached, and 
its utilisation by Mr. Frederick Burlingham for 
kinematographic work, promise to furnish a means 
by which the rival views concerning the nature 
of the volcanic gases may be put to a crucial 
test. The floor of the present crater of Vesuvius 
lies at a depth of about r1ooo ft. below the crater- 
rim; in this floor a funnel-shaped opening 200 ft. 
deep was opened last July, after the volcano had 
sunk to the solfataric condition following the 
Copyright) 
problem has appealed to vulcanologists with 
greater force than that concerned with the nature 
and origin of the gases which produce explosive 
action in volcanoes. That water-gas appears in 
enormous quantities during explosive eruptions 
cannot be doubted, for it is condensed in heavy 
rain-torrents; but it is by no means certain that 
these abundant watery vapours may not be due, 
wholly or in large part, to moisture derived 
originally from the atmosphere. M. Brun regards 
the long prevalent opinion among geologists—that 
the hydrochloric acid, sulphurous acid, nitrogen, 
and other gases, which are undoubtedly present, 
NO. 2310, VOL. 92] 
Fic. 1.—Fumaroles on south-east crater wall, showing steepness of crater-wa'l inside. 
(A. Burlingham. 
great and destructive eruption of 1906; at the 
bottom of this funnel (1212 ft. from the summit 
of the volcano) considerable, and apparently in- 
creasing, activity is taking place. It remains to 
be seen whether this activity will eventuate in the 
formation of a cone rising from the present crater- 
floor, or in a violent paroxysm that will carry 
away the crater-floor and increase the depth of 
the cavity. 
By the courtesy of the British and Colonial 
Kinematograph Company and of Mr. Burling- 
ham, Nature is able to publish examples of the 
| interesting photographs obtained during their 
