frequently found in the northern provinces of Friesland and Groningen; scoop wheels
are generally to be found in the south. Both these models were intended to work, and
the bases are painted to resist water.
The Directors’ minute of 5 November, 1790, is for a “Vijzel Watermolen” from
Cats costing ƒ 400. Van Marum made this entry in his journal on the following day:
“ Model van een Schroefmolen met de Molenwinden van Spille, en de wieken van van
Dyl, voor f 400” (MV). Cats was paid ƒ 300 on 31 December, 1790, and ƒ 100 by
February, 1791. The States of Holland granted, in October, 1780, a patent to Jan and
Harmanus van Deijl for a new type of lattice work for windmill sails. The patent
was renewed in 1795. This seems an unusual invention for optical instrument makers;
see Cat. 264.
Doorman (1942) patent H 265; Stokhuyzen (1965) 40—43.
Inv. 16/2
72 SAW MILL 1793 (45) Fig. 69
By Jochem Cats, Amsterdam
Signed at the back of the head: Mr I Gats 1793
Octagonal base measuring 510 between sides, height to top of cap 480, with finial 520;
diameter of sails 650.
The saw mill (houtzaagmolen)4s normally known in Holland as a paltrokmolen, after the
version developed in the Zaan district from about 1600. This type of saw mill is
constructed at the water’s edge, so that logs can be lifted from the surface where they
are stored. A hoist lifts the logs onto the platform when they are passed through the
saw. Here the saw blades are moved vertically by a crankshaft driven by the sails.
The hoist is also worked by wind power. I p protect the workers: there is a wooden
screen and penthouse, open at the back or leeward side. In the model, made chiefly
of mahogany, the main structural timbers only are shown, no weather boards being
fitted. The mill is rotated from the ground level, and at the rear is a capstan wheel,
The Directors’ minute of 22 June, 1792, is for a “houtzaagmolen” from J. Cats
costing ƒ 400.
Stokhuyzen (1965) 49—52,
Inv. 7/3
73 DREDGER *792 ..'JB38) Fig. 70, 71
By Jochem Cats, Amsterdam
Signed behind the hand-crank: MR I GATS 1792
Base 400 x 275, overall height 545.
Constructed mainly of mahogany, with some boxwood, this working model of a bucket-
chain dredger is described in the Inventory as an “ Amsterdamschen Moddermolen” .
This type of dredger is intended to be used attached to the side of a barge into
which the buckets discharge.
The accounts show that payment ofƒ 180 was made in 1792 to J. Cats for a model
chain mill (kettingmolen). They also record that ƒ 12 was paid §0 Cats for repairs
to this model in October 1792. It is not certain whether this refers to the dredger; see
also Cat. 75, and Inv, 16/3,
Inv. y/i
1 79