134 REPORT—1858. 
diate sense of nausea, amounting to vomiting in many cases. In the late earth- 
quake at Naples (Dec. 1857) many instances were related to me by the sufferers. 
The question arises, Is the nausea an effect of the sudden disturbance of the 
nervous system by alarm, &c., or is it due to the movement itself, and analogous 
to sea-sickness? There are great difficulties in the way of either solution. Those 
most likely to suffer severely from nervous alarm, do not seem to be those most usu- 
ally affected. The direct movements are very generally too sudden, sharp, and of 
too little duration, to admit of the second explanation. The facts, however, require 
to be more numerous, and to be scientifically collected and classified as soon after 
the occurrence as possible, and are commended to such physiologists as may be 
favourably circumstanced for the observation in earthquake regions. 
Indirect estimation of the force due to the shock.—In our ignorance of the precise 
nature of the originating impulse, whether of one or of more than one sort, or of the 
degree of force at the centre of impulse necessary to transmit a wave, sensibly, to a 
given distance through the common formations of the earth’s crust, any trustworthy 
observations, of the distance to which the very analogous blow produced by fired 
mines, or other masses of gunpowder, has been sensibly conveyed, are not to be 
at present neglected. The 2nd Report gives exact information as to the distances to 
which such impulses from fired powder, even of a feeble character, may be conveyed 
through the worst conducting material (sand), and made instrumentally sensible. 
I have collected since that period a few occasional notices of the explosions of 
large masses of gunpowder, and of such facts as may be found, of the magnitude and 
distance of the impulse conveyed, which I here transcribe for reference. It would 
be very desirable that officers of engineers entrusted with demolitions, or requiring 
to explode very large masses of powder, would endeavour to provide for obtaining 
observations as to the precise radius of the superficial area at which the ground 
shock became insensible without the aid of instruments, and that such observations 
were accompanied by a general account of the nature of the geological formation, 
and of the physical features of the country around. 
‘The Monster Blast at Furness.—The monster blast of gunpowder at Furness 
Granite Quarry took place on Wednesday afternoon, with complete success. The 
charge consisted of no less than three tons of gunpowder, and was deposited in two 
chambers—-one and a half ton in each. The shaft was 60 feet in depth, and the 
chambers in which the powder was placed were 17 feet long. The charge was 
ignited by a galvanic battery, and lifted an immense mass of rock, computed to have 
been between 7000 and 8000 tons. The flame belched out on the seaward side, 
and was well seen by a large concourse of spectators from Inverary, the watering 
places of the Clyde, and a party of excursionists from Glasgow, on board the ‘ Mary 
Jane.’ The report was not loud, but deep and hoarse, and the ground in a very wide 
circle was strongly agitated.”—Glasgow Constitutional, October 5, 1852. 
The ‘ Journal de Turin’ of the 29th ult. has, under the head of “latest intelligence,’’ 
the following paragraph :—‘‘'T'uRIN, 11°45 a.m. Two successive shocks have been 
felt like those of an earthquake. The powder magazine of Borgo Dora has ex- 
ploded. The population is hurrying to the scene of disaster. The rappel is being 
beaten. All the faubourg is on fire. A barrack has fallen down. Two hundred 
deaths are spoken of.””—Saunders’s Newsletter, May 1852. 
It is quite probable that both in this case and in that of the magazine at Mayence, 
which subsequently exploded, information might still be obtained as to the weight of 
powder fired and the extreme distance to which the shock was felt. 
«Improvement of the Port of Brest.—The ‘ Moniteur de la Flotte’ states that M. 
Verrier, engineer, charged with the work of clearing away the Rose Rock, which 
obstructs the entrance of a part of the harbour of Brest, called the Penfield, made 
an experiment a few days ago, which was perfectly successful. One of the convicts, 
covered with a diving-dress, descended to the rock at half-tide, and deposited a box 
full of gunpowder, to which were fitted two gutta-percha tubes, also similarly filled. 
As soon as the man had come up, a light was applied to the tubes, and shortly after 
a loud cracking noise was heard, and a large column of water, with fragments of 
stone and a quantity of sand and mud, were thrown up to the height of 20 feet. 
The commotion was so great, that the Bastion de la Rose, which stands near, 
