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nary lead line ceased to be available, or at all events convenient ; and until 
very recently the difficulty of calling up a long line and heavy weight from 
considerable depths was so great that it had become the practice to leave 
the weight behind, simply bringing up the specimen of the bottom. The 
Admiralty had made great improvements in deep sea soundings, but even 
with the rope now used its resistance to the water when drawn up by hand 
at considerable speed was so dangerous as to necessitate the use of steam 
power. When there was great resistance to the line, and the currents 
carried it away to a distance, it was difficult to know when the bottom was 
reached. However, he believed that with so great a weight as 3 cwt. the 
bottom might practically be perceived within a few fathoms, and, although 
it must be difficult to stop the line all of a sudden, he did not think the 
error in the sounding could be considered to be serious. To many it had 
occurred that wire rope would be a great advantage, inasmuch as it would 
occupy much less space and, therefore, create less resistance to the water. 
The objections Tvhich had been raised to wire were, that it was liable to rust, 
that the men could not handle it as it would kink, and it would go down in 
a heap over the weight ; but he believed all those difficulties might be 
overcome by proper care. It had been considered necessary to have a great 
deal of mechanism, but all that he deemed to be essential was a wheel 
which operated like a break, and around which the wire should be twined ; 
the wire used being No. 22 gauge, of the quality known as the homo- 
geneous steel wire, which could be manufactured in great lengths, was 
•03-inch in diameter, weighed 12 lbs. per statute mile, and broke with a 
weight of 252 lbs. To the end of the wire was attached a piece of hemp cord, 
which carried the weight, and by that means the wire was prevented from 
touching the bottom at all. He had made an experiment in mid-ocean, at a 
depth of 2,700 fms., experiments with the apparatus and materials he had 
indicated ; and, it having been attended with the most perfect success, he was 
sanguine that, if wire were allowed to take the place of cord in deep sea 
soundings, it would be far more economical, and so the calculations them- 
selves would be more accurate. 
Aerial Navigation . — This formed the subject of a paper read at the 
British Association in Brighton by Mr. C. A. Bowdler, in which he 
expressed the opinion that the autumn manoeuvres would be an excellent 
opportunity of trying experiments, and that aerostation would become an 
important element in military science. , Hitherto, captive balloons only had 
been used, but it was by no means improbable that circumstances would 
occur where it would be most desirable to pass over the enemy’s position, 
and it would then be important to have the power of severing or deflecting 
the balloon from the wind-course, either to right or left as required. Cap- 
tive balloons could not be used in safety in high winds on account of 
violent rocking of the car. The writer then proceeded to review the 
elements of aerostation, and to show that aerial navigation was practical to 
a certain limit by simple mechanical means. Of the practicability of apply- 
steam power he had no hope, the weight of a steam engine made as light as 
possible, consistent with due strength, being much too great for any gas 
balloon to support. The power he proposed was manual, being, he believed, 
the only power applicable to gas balloons. But propulsion having been 
