Combined vulcanite and steel sheathing.
There were also some other small matters wherein authorial energy busied itself.

But although I had models made of some, and wrote about others, no good results accrued to me.1.As for the horse-shoes, blacksmiths did _not_ want to lose custom by steel saving the iron.2.For the glass-stoppers, I had against me all the cork trade, and the wine-merchants too, who recork old wines.3.The steamers were never tried on a large scale, and models are pronounced deceptive.4.The coca loses most of its virtues when in a dried state.5.The pen (I had it made in silver, a long hollow handle ending with a conical point) either grew clogged if the ink was too thick, or emitted blots when too thin.
6.

An establishment in Leicester Square has since worked on this idea.
7.

I also troubled the Ordnance Office, and had an interview with Sidney Herbert about two more futile inventions! one a composite cannon missile of quoits tied together: another of a thick vulcanite sheathing for ships, over either wood or iron.

I have letters on these to and from the office.