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nitre was the best and cheapest. Neither the sulphur nor the nitre could 
be perfectly pulverised, and there was great difficulty in thoroughly 
incorporating the three components. Various improvements had been 
devised in this branch of the manufacture, the most successful being that 
of Congreve, who introduced the use of a metal or parchment sieve. 
Most of the accidents in powder mills occurred at this stage of the man- 
ufacture. The inventor of the new powder was a large quarry-owner, 
who, being struck by the number of men accidentally maimed at their 
work, directed his attention to the production of a powder which should 
be equally powerful, and less dangerous than ordinary powder. After two 
years of patient experiments he had perfected his invention. The new 
powder much resembled the old in appearance, both in the large and small 
grain, but it was said to be much lighter, specifically, than ordinary 
powder, and also to be about thirty per cent, cheaper. Bulk for bulk, it 
was rather the stronger of the two, and the difference in effect where equal 
weights were used, was very remarkable, being so much in favour of 
Neumeyer's, and the explosive force was the greater, the more tightly the 
powder was rammed down. It burnt much more slowly than ordinary 
powder, and produced much less smoke ; both of these properties would 
render it very valuable in mining, and in military engineering. The 
diameter of the flame of ordinary powder was 8 times that of the grain 
producing it, while with Neumeyer's, each grain when burnt made a flash 
12 times its own diameter, When burnt in the air, it left a slight residue, 
but not when burnt in a confined space, as in a cannon or a rock-hole. 
Mr. Praeger further stated that he believed Neumeyer's powder had less 
sulphur than, and was not so highly glazed as, ordinary powder ; also that 
it was less hygrometric, or liable to suffer injury from damp, but that if wet it 
could readily be dried again with very little risk, and that it was equally 
powerful whether in fine dust, or in large grains. He then read some 
testimonials, &c, from various persons who had used the new powder, 
and who reported favourably of it, and he made a few comparative expe- 
riments with the new and the ordinary powder, to illustrate the slow rate of 
burning of Neumeyer's, the great heat produced by its combustion, and 
the little smoke evolved, as well as the all-important fact that when set on 
fire in the air, it simply burnt rapidly, without causing any actual explosion, 
thus giving ample time for any person to escape from the vicinity of a 
barrel or store of powder accidentally set on fire. Details were given of 
an experiment at the Crystal Palace, at which 35 lbs. of Neumeyer's 
powder were burnt in a small house erected for the purpose, and but little 
damage was done, while the same erection was subsequently almost blown 
to pieces by the combustion of 3 lbs. of ordinary powder. That very great 
explosive effects could be produced by Neumeyer's powder, when properly 
applied, was amply testified by numerous competent persons, who had 
employed it practically in mining and other operations. In conclusion, 
Mr. Praeger said that the powder had been invented about four years, and 
