vi PREFACE. 



are distinct in subject as well as in treatment from any 

 of my essays which have formerly appeared. 



I invite special attention to the second essay on the 

 Transit of Venus. The time is drawing near when it 

 will be too late to take action to extend and render 

 complete and satisfactory our preparations for this im- 

 portant phenomenon the most important, I venture 

 to assert, of all the astronomical phenomena of the 

 present century. Without imputing blame to any per- 

 son, I must dwell strongly on the fact that the share 

 proposed to be taken by Great Britain in the observa- 

 tions of the transit, is unworthy of her position in the 

 scientific world, and as a nation. There is great risk 

 that, for want of an adequate number of southern sta- 

 tions, the whole series of observations by all countries 

 engaged in the work tvill result in failure; and it 

 appears to me nay, more positively it certainly is 

 a deplorable circumstance, that while Russia and 

 America are providing for more than thirty northern 

 stations, whereof sixteen are Halleyan, Great Britain 

 will supply but three southern stations, of which only 

 one chances to be Halleyan as well as Delislean ; while 

 even as respects this one station, Mr. Groschen has told 

 the country, speaking in his place in Parliament, that 

 either Halley's method c will not be applied at all, 

 or at least very little reliance will be placed upon it.' 

 Yet at sixteen northern stations, some of them most 



