Antique barothermograph principally constructed in lacquered brass with blued steel screws and pivots.  The barograph section driven by a seven cell aneroid pressure sensor acting on pivoted levers causing deflection of the light alloy recording arm, original bucket pattern pen, the recording drum with platform escapement and 8 day movement, captive key winding, regulation aperture, sprung paper retaining bar, dust lid. The thermograph of similar construction but driven by a Bourdon pattern heat sensor fitted to an oxidised brass bridge. Original bucket pattern knib. All raised on turned pillars set on a full length chassis having arrestor bar, twin ink stations with original bottles and dippers, adjustment knobs marked “Baro” and “Therm.” Retailer’s plate to front marked “A&NCS Ltd, Westminster.”

The whole barothermograph contained within its well executed mahogany case comprising bevelled five glass cover, the base with frieze chart draw.

The subject of a near complete overhaul, the chassis and majority of the brass work struck back, grained and re-lacquered, the movement with re-cut and finely ground pivots, the mechanism re-aligned and balanced, both sections re-calibrated. One of the ink stations replaced.

Chart from w/c 5 Nov 2018, showing a depression moving through Shropshire, the temperature remaining steady as the barothermograph is in a controlled environment

These instruments may be considered scarce, as they were almost twice the price of a conventional barograph recorder. This one is now probably performing above specification due to the very fine tuning and adjustment it has received, and is capable of resolving very fine detail. In very good condition and full working order.

This barothermograph, almost certainly made by Negretti & Zambra, and retailed by the Army & Navy Cooperative Stores Ltd, is an instrument of far superior construction to the majority and the use of a Bourdon tube to energise the thermograph is a much more expensive option. A real collector’s piece.

NB: The Negretti & Zambra barograph instructions shown below are part of our archive of historical materials – a copy of this original document will be included with this barothermograph.

Dimensions: 14″ long x 9″ high x 8½” deep

Stock No: BG0703

Price: SOLD