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MINUTES OF PEOCEEDINGS OF 
the 600-pr., and there is reason to believe that with the 700-pr. a new 
description will be required. It is not improbable that it will be found 
necessary to adopt two sorts of different densities, one of which shall be 
suitable for the smallest of our heavy guns, and the other for the heaviest. 
Mixtures in different proportions, it may be conceived, will meet the require¬ 
ments of the intermediate natures. Prom past experience we should take a 
lesson not to rush on too hastily in an old groove, making large quantities 
of a powder which, though well adapted to present requirements, may soon 
become obsolete as the art of gun-making advances ; for if we do, we may 
again find ourselves with plenty of powder, but with very little of the precise 
nature we require. 
III. How TO DO IT. 
The importance of determining the questions I have briefly sketched out 
will readily be recognised, but the question may be asked. How are we to 
do it when so many have failed? We must benefit by the experience of 
those who have gone before us, and, if possible, improve on it, taking care 
to avoid their failures. Bodman had a clear idea of how a systematic series 
of experiments ought to be carried out when he varied the length of charge, 
column of shot, and diameter of bore. It is because Mr. Bashforth followed 
a similar principle when he carried out his experiments with varied bores, 
charges, and projectiles, to determine the resistance of the air, that he has 
met with such marked success. Had Bodmaids pressure-gauges been as 
accurate and as sensitive to determine pressures as Mr. Bashforth's instru¬ 
ment was to determine time, we should not have had much more to do than 
accept his conclusions. But Bodman failed for want of an instrument to 
carry out his ideas. He has, however, shown us what is to be done. Let 
us but carry out his notions on the plan laid down by him, and we shall 
obtain results which will well repay a little trouble and some expense. 
It would be necessary to have experimental guns of the strongest possible 
form of construction, and of varied calibres—say 3, 5, 7, 9, and, possibly, 
11 ins. 
Pebble powder being most likely to give satisfactory results, should first 
be tried. Density, also, appearing to be the most important element, should 
first be investigated. Two densities of this powder might be used, 1*74 and 
1‘84. Commencing with density 1*74, it should be fired first from the 
3-inch gun, with varied charges and projectiles, noting the increase of 
pressure for each increase of charge and each increase of projectile, and 
taking care to note any manifestation of anomalous pressure. 
The same powder should then be tried, in the same manner, with the 
5-inch gun, and the pressures noted, with the view to find out whether they 
increased with the lengths of charge and projectile in the same way as in 
the 3-inch gun, or at a more rapid rate. 
The same should be done with the 7-inch gun, to see if the pressures 
were the same, or increased at a still more rapid rate, and so on with the 
9-inch and 11-inch guns if necessary. 
Density 1*84 should be tried in a similar manner, and in all probability 
will show that the pressures are less under similar circumstances, and that 
longer columns of powder and shot can be fired with this powder than with 
density 1*74. 
