No. XI.
Reading edition
How to prevent and safeguard any ship from such an attempt by day or night.
NOTE.
A safe and easy method of preventing the dreadful consequences attendant on the explosion of this tremendous machine, may be found in the use of a strong net, resembling that used in the salmon fishery; which must be kept at the required distance from the vessel by floating buoys placed for that purpose. It will also be necessary to fix a bell upon the upper extremity of each buoy, which will, by its ringing on a calm night, discover the approach of any hydrostatic vessel; and should the weather be stormy, the attempt must end in the destruction of the sub-marine voyagers.