TRANSACTIONS OF SECTION G. 1201 
4th. The question of the use of thick plates for boilers was discussed, and the 
results of a series of experiments were given, which go to show that if the 
material is carefully made and tested, heated in proper furnaces, and bent without 
putting any undue strains upon them in the boiler maker's shop, it was just as safe 
to use plates for boilers from 1” to 14” thick, and weighing from 1 ton 10 cwt. to 
2 tons 10 cvt., as it is to use those from 2” to 1’ thick and weighing from 10 cwt. 
to 1 ton 10 ewt. 
4. The Diminution of Casualties at Sea. 
By Don ArttrRO DE Marcoartv. 
The author in his paper made the following proposals:—1. That vessels be 
supplied with apparatus to communicate with and to telegraph to each other and 
to the nearest coast the weather and sea encountered by them; 2. That the 
steamers give more detailed reports about the weather and sea as soon as they 
arrive on both coasts, but more especially on the American cvast, to the Navy 
Department and to the U.S. Signal Service; 3. That a special, regular, and 
permanent service be established on the American coast, supplied with the requisite 
means to receive all reports, and to transmit to Europe several warnings each day 
about the reports collected and the predictions bearing on the navigation; 4. That 
from the European coasts be communicated daily to the American coasts the state 
of the weather and sea for comparison with the predictions and for the continuous 
study of the sea and weather. 
For advancing meteorological knowledge, and in the interest of navigation, he 
recommended the establishment of two more cables—one to connect Iceland and 
the Faroes with Europe, the other to connect Azores and Bermuda with Europe 
and America; as all the submarine cables connecting North America and North 
Europe have not intermediate stations on the middle Atlantic, and the great 
extent of the ocean renders reporting impossible. 
In the charts of relative storm frequency in the Northern Hemisphere, prepared 
by the American Signal Service, and published only a few months ago, it is shown 
in the annual average of the relative storm frequency during twenty-one years, 
from 1864 to 1884, that the sea is most calm between the meridian 40° and 9° 
(near to the Iberian Peninsula), and from latitude 40° at the first meridian to 
latitude 46° at long. 1°; and stormy towards the latitudes of Newfoundland, and 
ascending from their parallels to the north of Ireland. 
The last limit of the most frequent icebergs, according to the observations 
collected by the Hydrographer of the United States Navy Department, was near 
40° latitude ; and therefore the track from the United States to Lisbon is to the 
south of the icebergs. 
Professor Graham Bell published a few months ago the results of some experi- 
ments to detect by echo the proximity of vessels and wrecks. The experiments 
were made on the River Patapsco, about seven miles from Baltimore, The apparatus 
employed consisted of a musket, to the muzzle of which a speaking-trumpet was 
attached. From this musket blank cartridges were fired when passing vessels, and 
after a longer or shorter time, according to the distance of the vessels, an echo was 
returned, 
The author called attention years ago to the great power of ice for reflecting 
sound, and believes the possibility of obtaining an echo from an iceberg, when 
in dangerous proximity to a ship, is worth a trial at sea. Both apparatus, the 
thermopiles combined with the trumpet, and the steam-whistle and siren, ought to 
be used ; but it is better to select a route away from bergs, fields, and fogs, which 
have caused the loss of so many vessels, Parry says, in the account of his Polar 
Expedition, that two men conversed distinctly at a distance of a mile and a 
quarter. 
Fires. 
To lessen the risk from fire ‘automatic sprinklers for fire extinction’ and ‘ fire 
alarms’ are required in some parts of the ship, especially in connection with 
inflammatory goods, 
1885. 44 
