When I was gathering material for my book, Find and Destroy: Antisubmarine Warfare in WWI (Naval Institute Press 2001), I acquired this leather-bound manual.
The Explosive Paravane, or Submarine Sweep, was a towed device that was issued to destroyers and trawlers during WWI, as illustrated in this diagram from the Manual.
It could be exploded on contact or remotely from the towing ship. A sweep contact, of which only one occurred in WWI, is shown here in a drawing from my book.
The explosive paravane was launched much like putting a lifeboat in the water. The tricky part was heaving it aboard because the charge was armed and set to explode on contact. This diagram is also from the manual.
This is what the device looked like. It was 6-feet, 3-inches (2 m) long and 20-inches in diameter (80cm), and packed a 400-pound TNT charge in the nose. The spinner on the nose armed the charge much like a falling bomb.
Cmdr. C. Dennis Burney, RN, invented the explosive sweep and its sister, the mine-sweeping paravane that is still in use.
As with every book I have written, I built a 1:8 model and acquired some representitive artifact or artifacts. In this case the Vickers manual is the artifact. Dwight