J. Th. Verstelle The small Lucas Sounding Machine: and some of its defects in practice when the machine is in use for a length of time PDF (English)
J. Baillaud On the Graduation Errors of Circles used in geodetic operations: and on Methods which make it possible to reduce their influence PDF (English)
Ernst Römer Aggregation of Stationary Current Overfalls in the waters of Northwest Africa PDF (English)
André Blondel On the use of Yellow-tinted Glasses in the design of Maritime or Aviation Lighthouses PDF (English)
