Proceedings 29         6 October 1992        the Warburg Institute

MEDIEVAL MOUSETRAPS: a paper by David Drummond, former head of the UK Rodent Research Department and Director of the Central Science Laboratory.

The President welcomed members and visitors before introducing the speaker.


In 1590 there appeared A booke of engines and traps to take polcats_buzardes, rattes, mice and all other kinds of vermine and beasts whatsoever, most profitable for all warriners, and such as delight in this kind of sport and pastime. It was the last in a series of such books on household management by Leonard Mascall, Clerk to the Kitchen to the Archbishop of Canterbury, who had died tne year previously and had clearly used many earlier sources now lost. Apart from a few isolated descriptions and illustrations, Mascall's compilation was the earliest substantial body of information on its subject.

In all he described 9 recipes for poison baits and 34 different traps 12 of them mousetraps: in all but two cases, which required some adjustments, It had been possible to make working models by following Mascall's descriptions to the letter.

1] A Mill to take Mice (M.pp,77-78):--an indoor type of pitfall trap comprising a spindle fitted with baited vanes and mounted at the edge of a table overhanging a bucket of water. Trying to take the bait the mouse would over balance and plunge to a watery grave. Plastic traps using the same principle were still occasionally met with today but had little market success.

2] The mouce trap with a dish and filboll (M.78):--the 'filboll' was a wedge of wood with a three inch tail used to prop up the inverted bowl, the baited tail pointing to the centre. Going for the bait the mouse disturbed the fllboll, this would dislodge the bowl to fall and trap the mouse.

3] The square box trappe (M.84): a box was closed by a drop-fall sliding lio held open by a baited notched stick. Taking the bait (Mascall recommends cheese!) dislodged the stick, the lid fell and trapped the live mouse.

4] The double trappe to taKe Rattes or Mice (M.64-65):--two box traps, with a common side and entrances at opposite ends. Drop-fall doors were held open and released on disturbance by a 'strlng and clicket' mechanlsm, the clicket being a short length of wood with a bent wire carrying the bait and a string holding open the trap door. Variations of this mechanism were to be found in many other types of trap.

5] The fall for Rats and other vermine (M.72):--judging from the numerous representations in medieval paintings etc a most popular form of trap. A heavy wooden block poised directly above a bait, sliding between two uprights and held in place by a string and cllcket, fell to crush any rodent which dislodged the mechanism while going for the bait.

6] The square mouce trap (M.78):--a dead-fall killing trap similar to No.5

7] The followlng trappe for mice (M.81):--this had an upper board held up by a string and clicket released by a treadle with in addition a 'fllowlng staffe', i.e. a wooden rod powered by the torslon of twisted cods which drove the upper board down and held it down once the trap was sprung. The first known appearance of this type is in the depiction of St Joseph at his work bench In the Merode altarpiece by Robert Campin aka The Master of Flemaile (Met. Mus. Art N.Y.)--the trap on the open window shutter is of the dead-fall type.

The symbolism of these two traps was discussed by Meyer Shapiro in his 'Muscipula Diaboli'in Art Bulletin No 27 (1945) while in the 1960s controversy was provoked in the art world by the mistaken claim by Irving Zupnick ( 'The mystery of the Merode mousetrap', Burlington Magazine, 108, 1966) that the 'following trap' on the work bench was in fact a carpenter's plane. Unfortunately there was some confusion by the art experts as to the actual working of the device and John Jacob of Liverpool's Walker Art Gallery commissioned what he supposed was a replica in which the treadle (seen projecting from the front of the trap in the painting) was a prop for the upper board--even so he caught a mouse in the gallery with his device!

In fact the artist had depicted an incomplete trap lacking the string and clicket required to set it properly. This he did either from a desire for verisimilitude--what could be more natural than~ a carpenter having an unfinished piece on his workbench or, mere likely in the lecturer's opinion, because artists paid little attention to the actual construction of mechanical contrivances so long as they were identifiable by the intended contemporary viewer. Indeed the anonymous 16th century artist known as the Master of the Mousetrap' because he 'signed' works with a mousetrap emblem had made errors in the mechanism!

8] The Dragin trappe for Mice or Rattes (M. 71):--an early type of snap trap, the 5trlking frame being power by the torsion of twisted cords and set off by a treadle. The frame was fitted with a row of metal teeth looking like a 'dragin' or harrow. Similar designs were to be found in early Egyptian tomb paintings and (known as Nordo Baltic torslon traps) were also in use in northern Europe in quite recent times

9] The dragin trappe with a great wyar (M.75): - one stage nearer the modern snap trap, the 'great wyar' being a metal spring with the striking frame as a continuation.

10] The boxe trappe <M.73): - a guillotine type in which the mouse put its head in a hole to get the bait and thereby released the wire spring and striking frame.

11] The bow trappe for Rats or other Vermine (M. 69) : - an early form of guillotine trap, with a striker in the form of a solid piece of wood powered by a wooden bow. It was the most powerful of all the traps considered.

12] The Spring trappe for Mice (M.74): - a choker trap in which the victim put its head in a hole to reach bait thereby triggered a noose which rose to throttle it. Traps of this type had been as early as the Indus valley civilization of the 3rd millenium BC.

It was apparent from Mascall's book that the medieval mouse catch er had a wider selection of types of trap than that available to his modern counterpart, whether they were' more effective was another question. The reduction in the variety of traps available today was the result of the incorporating improvements in the technology of the intervening 400 years.

In Mascalll's day sources of energy to power the trap mechanisms included gravity, wooden bows, twisted fibres and simple metal springs These tended to produce clumsy designs which could be inadequate either in power or rapidity of action. More effective designs only became possible after the introduction of the helical spring in the early 16005 and the further development of a really strong miniaturized version still later. Similarly, although a short robust form of improved hinged clicket was known and described by Mascall in his 'griping trappe made all of yrne' for larger mammals, it was only after his time that it was reshaped and reposltioned for use, in conjunction with the helical spring, in smaller traps.

After question from the floor, the President brought the meeting to a close.

Digest G.S. Hindley, Sec SHMTS from text by David Drummond