Diagrams, magnetic ascending and descending changes by Stephen Joseph Perry and Balfour Stewart Two small diagrams showing 'true magnetic descending change' and 'true magnetic ascending change' and corresponding observed disturbance couplets. Subject: Magnetism Prints of these diagrams were published in volume 39 of the Proceedings of the Royal Society alongside 'Preliminary results of a comparison of certain simultaneous fluctuations of the declination at Kew and at Stonyhurst during the years 1883 and 1884, as recorded by the magnetographs at these observatories'. 1885