and Traverse Worker, *29 



be true • and at the same time it will doubtless detect any 

 errors occasioned either by miscalculation or nns-pnnted 

 ficTures, in any of the tables. Now as it will be readily granted 

 that the three sides of the octant represent the sines, tan- 

 gents, and secants of their opposite angles, it will thei-eiore be 

 plain, that all the solutions in navigation are obtained by the 

 Seaman's Octant precisely as by calculation; in which the 

 artificial sines, tangents, &c., with the table of logarithms, are 



^"rhTtiiis instrument would be found infinitely useful in 

 schools and academies, and particularly in naval schools can- 

 not be denied. It will give facilities for more readily in- 

 structino- youths in navigation; and not only relieve the mind 

 from the various hard and dry problems in trigonometry, in- 

 stead of clogging it; but it would doubdess furnish the pupil 

 with a far better idea of the nature and properties of triangles, 

 than the present method of instruction is calculated to altorcl ; 

 because the octant exhibits a demonstration to the sight, and 

 it would remind him at the same time continually ot what 

 he was about. Hence would the youth, while he was thus 

 amused with the instrument, at the same time improve and 

 expedite his progress imperceptibly in that valuable study 

 trigonometry, the basis upon which all the cases in navigation 



T"most perfect conviction that an instrument of this kind 

 may safely be used at sea, and that it would be found exceed- 

 ingly serviceable to men of science, land-surveyors, &c.; and 

 ako that it is an instrument generally useful to others, are the 

 chief reasons of its being now produced. It is mdeed truly 

 eratifyino- to add, that the Seaman's Octant has been approved 

 by testinTonials from some of the first scientific and practical 

 characters of the day ; and that it also has met the liberal sup- 

 port and approval of the Hon. East India Company, who have 

 favoured the inventor with an order for the same. Pertecting 

 the instrument has been for many years attended with incon- 

 ceivable difficulty and expense; it can scarcely, theretore, be 

 expected ever to give the inventor, in his life-time, anythmg 

 like a fair remunerating profit, from the very great pains 

 which have been bestowed on it. There is, however, a hope 

 yet to be indulged,-and it is this, to learn that Crow s Sea- 

 man's Octant and Traverse Worker has come into general use 

 throughout His Majesty's royal navy and the merchant ser- 

 vice To live long enough to know diat its use has extended 

 thus far, would indeed be a great inward gratification, and an 

 ample reward for any deficiency of pecuniary remuneration. 

 How few among that useful class of men, the plain practical 



