PROCEEDINGS OF THE BOARD OF REGENTS. 81 



work proposed, it is almost needless to dwell upon its value to science. The 

 one consideration, that Piazzi's obsei'vations must, for long years to come, fur- 

 nish the only means of determining the proper motions of more than five 

 thousand stars, is of itself sufficient. For the other stars observed by him, 

 they constitute a most important element in the determhiatiou. The huge 

 number of stars, observed in zones by Lalande, at almost the same period — more 

 than fifty thousand — depend for their reduction and value almost solely upon 

 Piazzi's results ; and the formation of a new catalogue of the latter will give an 

 altogether new value to the results of Lalande. The great mass of independent 

 observations thus rendered more accurate can speak for themselves, and it is 

 manifest that their usefulness will be far greater than that of the same number 

 of new observations made now. 



Unfortunately, Piazzi's observations do not afford all the elements now 

 known to be needed for their reduction, and it will doubtless be necessary to 

 reduce them differentially, thus greatly increasing the labor. Not merely ques- 

 tions -of azimuth, zenith point, and clock correction, but also questions of 

 graduation, of irregularity of pivots, and even of refraction, must be discussed, 

 thus rendering the undertaking one of no small magnitude ; still it would, I am 

 sure, be labor well bestowed, and, as Professor Argelander wrote me in 1857, 

 "it would be a grand thing, * * * * and one of the most important 

 things that could be done." 



The first process required is the reduction to the mean equinox of 1800.0 of 

 all the observations just as they were given by Piazzi. This is a work Avhich 

 could be carried on by ordinary computers, and would in itself be of great service, 

 even were the discussions of the observations to be omitted. It would consti- 

 tute nearly two-thirds of all the labor, and possesses the great advantage that 

 whatever is done, be the amount large or small, is immediately available. The 

 best estimate that I am able to make gives about $5,000 as the probable cost 

 of this reduction, to which from one-quarter to one-third should be added for 

 the expense of checking, comparing, and correcting mistakes. Therefore, be- 

 fore beginning, I desire to make sure that at least $6,000 will be available for 

 the purpose. There is scarcely a limit to the number of computers who could 

 be employed at once upon this part of the work. It might easily be accom- 

 plished in a single year, or it might be slowly and regularly carried on for a 

 long time, the expense being not very different in the two cases. 



This process being completed, the remainder of the work, consisting of various 

 investigations, in addition to the discussion of the instrumental corrections, and 

 the formation of a catalogue from the observations after all reductions have been 

 applied, would, of course, require more deliberate study. It would probably 

 occupy at least two years, but 1 think the expense would be decidedly inferior 

 to that of the first process. Indeed, I have convinced myself that all the out- 

 lays needed for the whole undertaking in all its branches Avoiild not exceed 

 $10,000, and that if this sum were now available, the Avork might be completed 

 in two years, inasmuch as parts of all the processes could go on simultaneously. 



My sense of the usefulness of this work, and my conviction that astronomers 

 everywhere would agree in this opinion, are so strong that I have determined 

 to appeal to you for aid, well knowing that your interest and moral support 

 will, under any circumstances, not be wanting. It is precisely such an under- 

 taking as the plan of the Smithsonian Institution would lead it to encourage ; 

 and although I can readily see that the amount needed is larger than the Smith- 

 sonian would probably be able to apply at any one time to the furtherance of 

 any one science, still I come to you './ith my plan, well assured that you will 

 willingly do what you can in its behalf, whether by some gradual appropriation 

 year after year, from the Smithsonian funds, in aid of what I have called the 

 first process, viz. : The computation of the correction to the mean equinox of 



6 s 



