In 1754 and 1757, Brahms published a two-volume book on dike maintenance, the Anfangsgründe der Deich und Wasser-Baukunst [Principles of Dike and Aquatic Engineering]. In it he recommended regularly comparing the height of the dikes with the high tide level.[5] He kept the first known records of the tide levels on the North Sea coast of Germany, and established records of storm surge levels.[6] He also developed mathematical models of local wave heights as being proportional to the square root of water depth[7] and of the motion of sediments in water channels.[4]