32 REPORT—1863. 
tar. Not only is our chief supply of ammonia, the food of plants, derived from 
that source, but those brilliant and varied colours which are now so much in use 
for dyeing silk also owe their origin indirectly to the same source. There is perhaps ~ 
no more striking instance of the ‘benefits which ultimately arise even to the manu- 
facturing arts, from every complete investigation of chemical substances, than is 
afforded by those beautiful dyes which have sprung up today from aniline, which 
yesterday was a chemical novelty in the hands of a first-rate investigator. 
On some Results of Experiments on Lucifer Matches and others ignited by 
Friction. By Professor Axe, FB.S. 
Having mentioned the components of the frictional composition, or the heads 
of the principal English and Foreign matches, he went on to notice the possible 
causes of accident in the transport of matches. The result of experiments proved 
that no degree of heat to which, under all ordinary circumstances, matches were 
likely to be exposed in their transport or otherwise, would suffice to lead to their 
spontaneous ignition. It was quite within the range of possibility, however, that 
on board ship continuous concussion, combined with a degree of heat, might bring 
about accidental ignition of matches, while it might be granted that the accidental 
ignition of one or two boxes in securely closed cases might frequently occur almost 
without a possibility of fear of its spreading to other boxes. A knowledge of the 
causes of the accidental ignition of gunpowder and other explosives rendered it 
advisable that such precautionary measures as were obvious and easily observed 
should be attended to in the shipment of matches, with the view of reducing such 
occurrences to the minimum extent. Some of those steps he specified. The first 
was the pHa gl of a place for the reception of such packages, distinct from 
all other merchandise. Secondly, the efficient ventilation of that part of the vessel 
in which matches were stowed. Thirdly, the enforcement of rules to prevent fire 
being brought by sailors within the vicinity of the matches. Fourthly, the care- 
fully packing of the match-boxes into cases, so as to prevent any independent 
motion. And, fifthly, the bestowal of more uniform attention on the production of 
mt and sufficiently stable match-boxes, and on the packing of the matches into 
the boxes, 
On the Impurities contained in Lead, and their Influence in its Technical Uses. 
By W. Baxer, F.C.S8. 
Having noticed the characters by which pure lead is known, the author proceeded 
to point out the impurities which render it hard, and what elements may exist in 
it without impairing the qualities which render it suitable for its various technical 
uses, The substances which commonly impart hardness to lead are sulphur, anti- 
mony, and arsenic. Copper, if alone, does not much affect the softness of lead. 
Tron also, in the absence of sulphur, is not found in sufficient quantity to produce 
hardness. Refining processes for impure lead are essentially oxidizing processes. 
When the antimony is not more than 1 to 2-070, as in Derbyshire slag-lead, the 
igs are placed on the bed of the ordinary reducing furnace and melted down with 
free access of air, The separation of the lead from its impurities being effected by 
taking advantage of the difference between the melting-points of lead and the mixed 
sulphides, the latter are left on the bed of the furnace, whilst the purified lead in an 
oxidizing atmosphere runs into the pot. The writer has introduced an oxidizing 
agent for effecting the softening of slag-lead as it is tapped from the blast-furnace. 
The softened lead is treated by Pattinson’s process for the concentration of silver. 
It is highly important for certain technical uses that lead should be practically free 
from copper. Less than 2 oz, per ton will produce a pink tint on white-lead cor- 
rosions, and good red lead for glass-making should not contain more than 1 oz. per 
ton. » 
On the Manufacture of Aluminium. By I. L. Beri, Mayor of Newcastle. 
The progress of the manufacture of this—so far as the arts are coneerned—new 
metal has scarcely been such as to require much to be added to those admirable 
