Curiosities of Science. 185 



have so taught him how to use these invisible couriers, that 

 they, with the calm belts of the air, serve as sign-boards to 

 indicate to him the turnings and forks and crossings by the 

 way. 



Let a ship sail from New York to California, and the next week let 

 a faster one follow ; they will cross each other's path many times, and 

 are almost sure to see each other by the way, as in the voyage of two 

 fine clipper-ships from New York to California. On the ninth day after 

 the Archer had sailed, the Flying Cloud put to sea. Both ships were 

 limning against time, but without reference to each other. The Archer, 

 with wind and current charts in hand, went blazing her way across the 

 calms of Cancer, and along the new route down through the north-east 

 trades to the equator ; the Cloud followed, crossing the equator upon 

 the trail of Thomas of the Archer. Off Cape Horn she came up with him, 

 spoke him, and handed him the latest New York dates. The Flying 

 Cloud finally ranged ahead, made her adieus, and disappeared among 

 the clouds that lowered upon the western horizon, being destined to 

 reach her port a week or more in advance of her Cape Horn consort. 

 Though sighting no land from the time of their separation until they 

 gained the offing of San Francisco, some six or eight thousand miles 

 off, the tracks of the two vessels were so nearly the same, that being 

 projected upon the chart, they appear almost as one. 



This is the great course of the ocean: it is 15,000 miles in length. 

 Some of the most glorious trials of speed and of prowess that the world 

 ever witnessed among ships that " walk the waters" have taken place 

 over it. Here the modern clipper-ship the noblest work that has ever 

 come from the hands of man has been sent, guided by the lights of 

 science, to contend with the elements, to outstrip steam, and astonish 

 the world. Maury. 



EKROR UPON ERROR. 



The great inducement to Mr. Babbage, some years since, to 

 attempt the construction of a machine by which astronomical 

 tables could be calculated and even printed by mechanical 

 means, and with entire accuracy, was the errors in the re- 

 quisite tables. Nineteen such errors, in point of fact, were dis- 

 covered in an edition of Taylor's Logarithms printed in 1796 ; 

 some of which might have led to the most dangerous results in 

 calculating a ship's place. These nineteen errors (of which one 

 only was an error of the press) were pointed out in the Nauti- 

 cal Almanac for 1832. In one of these errata, the seat of the 

 error was stated to be in cosine of 14 18' 3". Subsequent 

 examination showed that there was an error of one second in 

 this correction, and accordingly, in the Nautical Almanac of 

 the next year a new correction was necessary. But in making 

 the new correction of one second, a new error was committed 

 of ten degrees, making it still necessary, in some future edition 

 of the Nautical Almanac, to insert an erratum in an erratum of 

 the errata in Taylor's Logarithms. Edinburgh Review, vol. 59. 



