The Cunard Line, off the coast of Ireland, fire a blue light followed by two golden star rockets. The Ulster Steamship Co. fire three vertical lights, yellow, blue and red, followed by two Roman candles fired together, each throwing two yellow, two blue and two red stars.
These examples will give some idea of the variety of signals used; they are often followed by another signal, or rather have a suffix which if fired has a particular meaning. For instance, a red light after the signal may mean "All's well," or a green may signify a wish to communicate. Some lines bring the whistle into the signal and combine long and short blasts with pyrotechnic signals.
Besides the house signals there are some generally accepted signals used by all vessels. A blue light is the signal for a pilot in all waters, except those of the United States. It is curious, however, that no universal pyrotechnic signal of distress has yet been arranged, although in 1889 Mr. F. Crundall endeavoured to get a standard distress signal recognised by shipping throughout the world. This signal, which consisted of a Roman candle surrounded at the mouth by four lights which burnt simultaneously with it, was demonstrated before the Board of Trade, and was distinguishable across the Channel at Dover, but was, however, not universally adopted.
Another extensive field use of pyrotechnic signals at sea is in the fishing industry. Lights and rockets are used to communicate between vessels of the fishing fleets and with the carriers.
The use of such signals by the coastguard and the Life-*boat Institution and at harbours and ports throughout the world is also very great.
Another pyrotechnic store of the greatest utility is the line-carrying rocket, a device which has been responsible for the saving of thousands of lives.
The credit for suggesting this use of the rocket appears
