Pages 269-278, extracted from un unknown publication and stapled between paper covers. Inscribed on first page;
"C.A.Ilbert Esq. from Paul Ditisheim. Very cordially"
The paper briefly covers the historic attempts to counter the effect of barometric pressure changes on the rates of chronometers and the present day (1937) trials and equipment.
Illustration of the testing equipment used in the Neuchatel Observatory; "Appareillage pour l'observation des Chronometres sous diverses densites atmospheriques et dans le gaz hydrogene".