In 1896 The first cloud atlas containing photographic images was presented at the international meteorological congress. The images were produced in Uppsala by the photographer Henri Osti in collaboration with professor Hugo Hildebrandsson, in order to create objective and scientific images, rather than hand made illustrations. The atlas contained 16 prints of clouds, according to the classifications used in 1896. Todays cloud atlas contains approximately one hundred separate cloud forms. 

We have, however, found a window from a hotbed, believed to be constructed from Ostis old glass negatives. Emma Osti, the widow of Henri, found herself in a hard situation financially after the death of her husband. Before interrupted by archivists, she had washed off and sold hundreds of Ostis glass negatives to farmers and gardeners, who used the glass when building hotbeds and glass houses. 

We have made several attempts at locating Ostis glass negatives, but at this point in time, it is unknown where this important contribution to meteorology has ended up.

​