CHAP. II.] A IVIARINE SURVEY IN GENERAL 61 



shores of the world, where there is much trade, and to such 

 ports, harbours, and channels as are largely used in navigation. 



The necessity for these surveys increases to an enormous 

 extent every year, with the prodigious strides trade, more 

 especially trade by means of steam vessels, is taking. 



A steamer works against time ; her paying capabilities 

 largely depend on her getting quickly from port to port, and 

 captains will take every practicable short cut that offers, and 

 shave round capes and corners in a manner to be deprecated, 

 but which will continue as long as celerity is an object. A 

 channel wliich a sailing vessel will work through in perfect 

 safety, from the obvious necessity of keeping a certain distance 

 off shore, for fear of faihng wind, missing stays, etc., will be 

 the scene of the wreck of many a steamer, from the inveterate 

 love of shortening distances, and going too near to dangerous 

 coasts only imperfectly surveyed. Better charts will not cure 

 navigators of this propensity, but will save many disasters by 

 revealing unknown dangers near the land. 



Time, and the comparative scarcity of marine surveys, do 

 not permit of keeping up to the rapid advance required in 

 this style of survey ; and unless the countries of the world 

 interested in ocean traffic largely increase their expenditure 

 on these matters, it seems as if charts will get farther and 

 farther behind requirements as years roll on. 



Having settled of what description a chart is to be, there is Detail 

 still much diversity in the method of undertaking the details variable. 

 of it. The extent of the work, whether simply a plan of 

 limited extent, or a large piece of oj)en coast ; the scale on 

 which it is to be done ; the nature of the coast and sea ; the 

 time and means at disposal ; the number of assistants ; will all 

 be considered in determining exactly how to set about the work. 



All this makes it very difficult to lay down rules for marine 

 surveying. Experience alone can dictate what should be done 

 in each particular instance. Though a plan may be produced, 

 the time employed, and the result of the labour expended, will 

 greatly vary according as to whether the work has been under- 

 taken in the right way or not, apart from any personal qualities 

 of the assistants, and nothing but the possession of the true 

 surveying " knack," combined with experience, will point out 

 this right way. 



