214 



DEPTHS OF THE OCEAN 



one of the founders of physical oceanography, used the surface 

 temperatures recorded from different places in the sea in his 

 examination of the currents. He organised an extended 

 collection of temperature-observations for the benefit of navi- 

 gation ; he studied the winds and the drift of vessels, and in 

 the middle of the nineteenth century he published his Ex- 

 planations and Sailing Directions to accompany the Wind and 

 Ctwrent Charts. He also wrote an extremely interesting book, 

 The Physical Geography of the Sea and its Meteorology, which 

 has appeared in many editions and in several translations. 

 Maury's work had important consequences, for ship-masters 

 following his directions shortened the voyage between North 



Fig. 153.— Benjamin P^ranklin's first chart of the Gulf Stream. 



America and England by ten days, that from New York to 

 California by about forty-five days, and that from England to 

 Australia and back by more than sixty days. The profit 

 derived from the use of Maury's charts by British ship-owners 

 on the East India route alone amounted to 10 million dollars 

 yearly. 



On Maury's suggestion it was decided, at an international 

 congress at Brussels in 1853, that numbers of log-books should 

 be sent out with captains of ships for the purpose of entering 

 observations of wind and weather, of currents, and of tempera- 

 tures at the sea-surface. This plan has been followed ever 

 since, the notes being as a rule entered once every watch, so 

 that a formidable pile of material has now been amassed. Up 

 to 1904 the Meteorological Office in London had collected 7 

 millions of these notes, the Deutsche Seewarte in Hamburg 



