A scientist whose speciality is hydrography.(noun)
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Use "hydrographer" in a sentence
"Ken Stumpf, supervising hydrographer for the Santa Clara Valley Water District, monitored water levels and potential flood risks last week."
"A year later, he defended his dissertation and obtained a lectureship at Göteborg Högskola, torn between work in radioactivity and hydrography, a conflict his daughter Agnes Rodhe has described as a struggle between his father's wishes and his own interests. 105 His position as a lecturer paid so poorly that he had to work as an assistant hydrographer at his father's oceanographic station in Bornö to supplement his income."
"The Expedition owes great obligations to the Lords of the Admiralty for their unvarying readiness to render us every assistance in their power; and to the warm-hearted and ever-obliging hydrographer to the"