15(3 Lieut. Maury's Plan for Improving Navigation. 



part of Lieutenant Maury's plan, as such, to send out survey- 

 ing expeditions. 



" Now, your Lordships will of course understand that other 

 things besides *the directions of the winds are contained in 

 these log-books, and these matters not contained in ordinary 

 records of this kind; but I thought it better to keep that 

 division quite distinct, as it is the winds that form the chief 

 guide in devising the new course. Hydrography is of two 

 kinds, — that which consists in accurate surveys of harbours 

 and coasts, which may be called more properly ' maritime 

 surveying,' and that which consists in recording all the 

 phenomena of a scientific character which are observed at 

 sea, in what sailors call ' the blue water,' i. e. out of ordi- 

 nary soundings. Among these the most important, exclusive 

 of astronomical and meterological observations, properly so 

 called, are the force and set of currents, and the temperature 

 and depth of the water. The American masters are instructed 

 to immerse a thermometer in the water, and take the tem- 

 perature of the ocean at least once a day, and to examine, as 

 often as convenient, the force and set of currents, and also to 

 try for deep sea soundings." 



Report of the Royal Society on Lieutenant Maury's Scheme. 



" Short as is the time that this system has been in opera- 

 tion, the results to which it has led have proved of very great 

 importance to the interests of navigation and commerce. The 

 routes to many of the most frequented ports in different parts 

 of the globe have been materially shortened, that to St 

 Francisco in California by nearly one-third : a system of 

 southwardly monsoons in the equatorial regions of the At- 

 lantic and on the west coast of America has been discovered ; 

 a vibratory motion of the trade-wind zones, and with their 

 belts of calms and their limits for every month of the year, 

 has been determined : the course, bifurcations, limits, and 

 other phenomena of the great Gulf-stream have been more 

 accurately defined, and the existence of almost equally re- 

 markable systems of currents in the Indian Ocean, on the 

 coast of China, and on the north-western coast of America and 

 elsewhere, has been ascertained. There are, in fact, very few 



