82 ANNUAL OF SCIENTIFIC DISCOVERT. 



terial. Though so very dissimilar to the substances generally used as 

 lubricants, its cleansing properties in the barrel of an arm are remark- 

 able ; it produces a beautiful glazing or surface upon the metal, which 

 prevents the adhesion of any of the residue. When pure it exhibits 

 no tendency to promote the corrosion of lead, nor cloes it undergo 

 by long preservation any change likely to prove injurious to the 

 metal. After the introduction of beeswax it was found necessary to 

 discontinue the use of the ordinary vegetable oils, applied to tne lubri- 

 cation of bullet-making machines, as it was discovered that even the 

 minute quantity of oil remaining upon the bullet after it left the 

 machine and had been cleaned was sufficient to establish a corrosive 

 action upon the lead. Recourse was therefore had to the neutral 

 and permanent lubricating oil prepared from petroleum. 



All are doubtless aware that voltaic electricity has been success- 

 fully applied, for some time past, to the discharge of mines. The 

 limits of my time will not permit to enter into details with respect 

 to the methods hitherto in use for calling into play the heating pow- 

 ers of the voltaic current to the ignition of powder, which, I may 

 just remind you, are based upon the resistance offered to the passage 

 of a voltaic current through a metallic circle by fine metal wires of 

 inferior conducting powers, such as iron or platinum. By tho intro- 

 duction of short lengths of such wires into those portions of the cir- 

 cuit which pass through the charges of powder, the passage of the 

 current will cause them to become heated to such an extent as to 

 effect the ignition of the powder. Although by such, or similar ar- 

 rangements, one or two mines may be discharged with certainty by 

 the direct application of the current obtained from a battery of mod- 

 erate power, more extensive, and particularly sub-jiiarine operations, 

 can only be effected by the employment of very powerful batteries, 

 and are even then attended with considerable uncertainty. These 

 circumstances, combined with the very great inconvenience and risk 

 of accident attending the transport of the battery and the acids and 

 other materials required to set it in operation, and the numerous 

 points to be attended to in order to ensure the full development and 

 application of the battery power, have led to the prosecution of nu- 

 merous experiments, in different continental States and in this coun- 

 try, for the purpose of rendering this particular application of electri- 

 city more certain and simple. Some successful results have attended 

 the use of the electricity of high intensity obtained by means of the 

 powerful electro-magnet coil-machines constructed by Ruhmkorff and 

 others. By their employment, with appropriate fuse arrangements 

 for effecting the ignition of the charge by means of the spark, the 

 battery-power necessary for firing a number of mines is very consid- 

 erably reduced. The most perfect of these coil-machines, even when 

 arranged in a form suitable for transport, are, however, very liable to 

 injury, particularly in the hands of those not thoroughly acquainted 

 with the principles and delicacy of their construction. Their em- 

 ployment, moreover, still necessitates the use of the voltaic battery. 

 Although, therefore, these machines doubtless admit of application 

 with great advantage in special cases, they are not likely to be gen- 

 erally substituted for the old arrangements. 



In Austria very important results are said to have been obtained 





