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'Seathwaite' Pattern Rain
Gauge
British Rainfall 1912, p.56
THE "SEATHWAITE" PATTERN RAIN GAUGE
In order to meet the peculiar difficulties of measuring the
rainfall in very wet and exposed positions where the gauges
cannot be visited frequently, an attempt was made last year
to devise a form of instrument which would be free from the
most objectionable features of existing rain gauges. To meet
the difficulty of collecting the whole rainfall for a month
in a very wet position the rim of the funnel was made with a
diameter of five inches, while the containing vessel had a
diameter of eight inches. Hitherto, gauges in which the
funnel was of smaller diameter than the receiver were open
to the objection of horizontal joints, the soldering of
which is particularly liable to give way and to allow rain
to enter. This difficulty has been overcome by attaching the
five-inch brass ring to a long and gently sloping cone
rolled out of one sheet of metal, so that it has only one
joint. Within this cone the funnel is fitted, its diameter
being naturally greater than five inches, and the lower end
of the cone is fitted over the eight-inch receiving vessel,
the sides of the cone projecting beyond the receiver and
coming down to within half an inch of the ground whene the
cone is in place. The cone is attached to the cylinder by
means of a separate device in the form of a bayonet joint,
which, when closed, cannot be opened until an extremely
inconspicuous brass catch has been pressed back. It is hoped
that this device will make the gauge less liable to be
tampered with, as anyone ignorant of the construction would
have great difficulty in discovering how to remove the cone.
The difficulty presented by the freezing of the contents in
winter or of evaporation of the water in summer, from a
gauge which is left for a month between visits, has been
attacked by making the receiver a cylindrical metal can,
fitting loosely inside the outer case, which is constructed
with double walls and double bottom, the intervening space
being packed with a non-conducting material, rendered
waterproof and sealed from contact with the air. This makes
the outer cylinder large and heavy, and when it has been
buried to the proper
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