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The most instinctive act of care a collector can offer an antique instrument — a drop of oil — is also the commonest cause of death among aneroid barometers. In a new illustrated essay, Leo Shirokov traces the lubrication problem from the watchmaker's bench to the conservator's table and explains why an instrument built by the means of horology must be serviced by the rules of metrology.
We have added a new long-read essay to the site: Lubrication in Historical Meteorological Instruments: Tribology, Metrology, and Restoration Practice.
Its starting point is personal. Over years of opening old aneroids, the most frequent cause of failure I have encountered was neither capsule fatigue nor wear, but excess lubricant applied with the best of intentions: a drop of oil on the pointer arbor that, decades later, has turned into a hard conglomerate of oxidized oil and dust, fixing the arbor solidly in its bracket; a bell crank flooded with oil until it stops turning at all. The essay asks why a gesture that is routine — and often necessary — in clockwork becomes destructive in a pressure-measuring instrument, and answers in the language of tribology: friction, stiction, hysteresis, capillary migration, and the ageing of oils all acquire a directly metrological meaning when the driving force is the flexing of an evacuated capsule rather than a mainspring.
Along the way the essay covers the history of precision lubricants from whale and bone oils to modern synthetics; the horological ancestry of the aneroid, from Vidie's patent of 1844 to jewelled bearings in precision altimeters; a classification of the movement into nodes that must stay absolutely dry and nodes that genuinely need oil; and a detailed chapter on the fusee chain — the most vulnerable part of the transmission — with a full conservation protocol for freeing a corroded chain (chelate cleaning, mechanical working, a dry microcrystalline-wax barrier) and an explanation of why oiling such a chain only makes things worse. Separate sections deal with barographs, with the conservation-versus-restoration dilemma, and with the special hazards of combined instruments, illustrated by a case study from my own collection: a Soviet Mayak wall clock with barometer whose open, barrel-less mainspring had once been oiled generously — and had then redistributed that oil over every part of both mechanisms.
The essay is illustrated with photographs of instruments and parts from the collection and closes with a bibliography of 26 sources, from Saunier and Britten to Bowden and Tabor and the Canadian Conservation Institute. It is available in full as a PDF on the site.