#JETTISON BILGE PUMP MANUAL#
On the subject of emergencies, which I sincerely hope none of us has to cope with, a large capacity manual bilge pump could be operated by the stronger members of the crew while weaker members could help by pumping the lower capacity ones. The bilge pump used for everyday needs, providing you do not have any serious leaks will not require a large capacity.Īnd a smaller pump will require less energy to drive it whether its manual energy or battery power. The table I have drawn up below gives an indication of the capacities you should be aiming for however, there are several other factors to take into consideration.įirst do they all need to be the same size? The next problem is deciding what size or pumping capacity your pumps should be. Where the water accumulates is another criteria to consider.Īny sealed compartments which do not drain to the bilges should have their own dedicated pump.Įven if these compartments will not hold much water it is worth having a small pump to drain them if only to prevent water damage. Next thing to consider is where the pumps are to be operated from.Ī cabin cruiser, for instance should have one which can be operated from the cockpit and another from within the cabin and again I'm referring to minimums. Pumps, 26 ft to 35 ft / 8M to 10M, at least three and anything aboveĮven on a small boat that one bilge pump is only adequate if it isīy the same criteria, larger boats should have at least one more than the minimum if only as a back up. Guide, a boat from 16ft to 26 ft / 5M to 8M in length should have at Brill, Leiden-Boston-London: 272-296.Even the smallest open boat should have some means of bailing.īucket, but only if he can get at it and is able to jettison it Wikander (ed.) Handbook of ancient water technology. Sherwood (1998) Greek and Roman technology: a sourcebook. In the same house, an inscription of a member of the collegium fabrorum (CIL XI, 2702) was found, the guild of builders/craftsmen, and it has been suggested that the pumps, which are fairly small, with an output of only +/- 0.25 litre per stroke, were display models, to show the possibilities and advantages. The museum’s force-pumps (1892,0517.,0517.2 and 2.a) were found together in a house at Bolsena, Roman Volsinii. Isidore of Seville, writing in the 6th/7th century AD, mentions its use to clean high ceilings. Smaller examples, like this one, were either display models for bigger versions, or part of a fountain or water well. The pump, the only ancient water-lifting device with a jetting delivery, was mainly used to fight fires, mounted on a cart with a reservoir of water and with a swivelling nozzle at the top of the vertical discharge pipe, or as a bilge pump, removing excess water from ships. A system of one-way valves made sure that the water went in the right direction, and the system of alternating pistons created a constant jettison of water. The pump would be placed within a body of water, and when the bar raised one piston, drawing the water into its cylinder, it lowered the opposite piston, forcing water out through the central outlet, which would be connected to a vertical pipe. Ktesibios’ force-pump was adapted by the Romans to include two cylinders, which would operate alternatively, but could still be handled by only one person and one handle bar. None of Ktesibios’ original writings survive, and we only know of his inventions through later authors, such as Vitruvius (On Architecture 10.7.1-4), Hero (Pneumatics 1.28) and Philo of Byzantium (Pneumatics, app. He worked at the famous library of Alexandria (some believe he was its first Head) under the royal patronage of Ptolemy II. At some point while building a system of pulleys for a moveable mirror, Ktesibios realised the potential of the force created by air when compressed and decompressed, and applied this both to machinery – inventing the first pump, but also advancing the theory behind the workings of a cannon – and to acoustics – inventing the first water-organ. Curator's comments The force-pump was invented by the Greek Ktesibios, the son of a barber.