AIDS OF THE NEWTONIAN PERIOD. 481 



Helena in 167*7, with the view of observing the southern stars, was at 

 his own expense ; but at a later period (in 1698), be was appointed to 

 the command of a small vessel by King William the Third, in order 

 that he might make his magnetical observations in all parts of the 

 world. Lacaille was maintained by the French government four years 

 at the Cape of Good Hope (1750-4), for the purpose of observing the 

 stars of the southern hemisphere. The two transits of Venus in 1761 

 and 1769, occasioned expeditions tG be sent to Kamtschatka and To- 

 bolsk by the Russians ; to the Isle of France, and to Coromandel, by 

 the French ; 10 to the isles of St. Helena and Otaheite by the English ; 

 to Lapland and to Drontheim, by the Swedes and Danes. I shall not 

 here refer to the measures of degrees executed by various nations, still 

 less the innumerable surveys by land and sea; but I may just notice 

 the successive English expeditions of Captains Basil Hall, Sabine, and 

 Foster, for the purpose of determining the length of the seconds' pen- 

 dulum in different latitudes ; and the voyages of M. Biot and others, 

 sent by the French government for the same purpose. Much has been 

 done in this way, but not more than the progress of astronomy abso- 

 lutely required ; and only a small portion of that which the comple- 

 tion of the subject calls for. 



Sect. 6. — Present State of Astronomy. 



Astronomy, in its present condition, is not only much the most ad- 

 vanced of the sciences, but is also in far more favorable circumstances 

 than any other science for making any future advance, as soon as this 

 is possible. The general methods and conditions by which such an 

 advantage is to be obtained for the various sciences, we shall endeavor 

 hereafter to throw some light upon; but in the mean time, we may 

 notice here some of the circumstances in which this peculiar felicity 

 of the present state of astronomy may be traced. 



The science is cultivated bv a number of votaries, with an assiduity 

 and labor, and with an expenditure of private and public resources, to 

 which no other subject approaches ; and the mode of its cultivation in 

 all public and most private observatories, has this character — that it 

 forms, at the same time, a constant process of verification of existing 

 discoveries, and a strict search for any new discoverable laws. The ob 

 servations made are immediately referred to the best tables, and cor- 



'» Bailly, Hi. 107. 

 Vol. L— 31 



