[March, 
Offensive and Defensive 
power varying from that of a glass of 4 inches focus to one 
of 2 inches. This means of varying the power at pleasure 
is valuable in dissection, especially when used with an 
erecting binocular microscope. 
VI. OFFENSIVE AND DEFENSIVE SUB- 
MARINE WAR.* 
By Capt. S. P. Oliver, (late) R.A. 
Part I. 
|jf N quaint old “ Pepys’s Diary,” under date of March 14, 
W 1662, we find the following entry “ Home to dinner. 
^ In the afternoon come the German Dr. Knuffler to 
discourse with us about his engine to blow up ships. We 
doubted not the matter of faCt, it being tried in Cromwell s 
time, but the safety of carrying themt {sic) in ships ; but he 
do tell us, that when he comes to tell the King his secret, 
(for none but the Kings, successively, and their heirs must 
know it,) it will appear to be of no danger at all. We con- 
cluded nothing: but shall discourse with the Duke ot York 
to-morrow about it.” And again, in 1663, as follows 
“ Novbr. nth. At noon to the Coffee-house where with Dr. 
Allen some good discourse about physick and chemistry. 
And among other things I telling him what Dribble the 
German DoCtor do offer of an instrument to sink ships ; he 
tells me that which is more strange, that something made 
of gold, which they call in chymistry 1 Aunim Fulmmans, 
a grain, I think he said, of it put into a silver spoon and 
fired, will give a blow like a musquett, and strike a hole 
through the silver spoon downward, without the least force 
upward ; and this he can make a cheaper experiment of, he 
says, with iron prepared.”— (“ Memoirs of Samuel Pepys, 
Esq., F.R.S.” Edited by Lord Braybrooke.) 
The doctors “ Knuffler ” and “ Dribble,” probably partners 
if not identical, do not seem to have been more successful 
* Torpedoes and Torpedo Warfare, by C. W. Sleeman, Esq., late Lieut. 
R.N., and late Commander Imperial Ottoman Navy. Portsmouth: Griffin 
and Co. 1880. , 
f “ Them” i.e., the said engines, which were evidently buoyant torpedoes. 
