276 OBSERVATORY AT CORDOBA, ARGENTINE REPUBLIC. 



— but there is one inhabitant of the i)ampas whose memory can never 

 fade. This is the vinchuca, an elder brother of that unnameable insect 

 whom Birdofredum Sawin found running away with his colonel in Mex- 

 ico 5 but it is a dozen times longer and broader and thicker, and far 

 more savage. And it has wings. By night this insect comes flying in 

 from all the open country round, and it seems to have a special predi- 

 lection for astronomers. But for them the observation of the summer 

 zones would have been easier. 



The plan of tbe zones was based, as I have said, upon the funda- 

 mental idea that the determinations should be absolute in their character; 

 still it is by no means certain that one observes under the high nervous 

 tension inseparable from such work in the same manner in which he 

 would make a leisurely measurement of the position of an isolated star. 

 It has, therefore, seemed desirable that the positions of not less than 

 SIX or seven stars in each zone should be determined with all possible 

 accuracy, and by means of repeated observations. With this view I 

 prepared a list of a few thousand stars, whose places were to be meas- 

 ured on not less than four nights, as opportunity should offer; and 

 the intervals between the transits of the fundamental stars, as well 

 those nights or parts of nights on which flying clouds or mists preclude 

 the zone work, although the heavens are partially clear, have beeu 

 devoted to this class of observations. Already a very considerable 

 amount of material of this sort has been collected and computed, and 

 this work is now going on in my absence. 



Among my most cherished hopes, when leaving home, was that of 

 supplementing in the southern hemisphere the remarkable and import- 

 ant results obtained here by our gifted countryman, Mr. Rutherfurd, 

 whose ingenious methods and surpassing skill had enabled him, and 

 him alone, to obtain photographic impressions of star-clusters with a 

 sharpness permitting delicate measurements, as well as to execute these 

 measurements with such an accuracy as to yield results rivaling, if? 

 indeed, not surpassing, those afforded by direct observation with the 

 most elaborate and costly instruments, and with a hundredfold greater 

 expenditure of time. It had been my privilege to subject these measure- 

 ments for the first time to those numerical computations by which the 

 stellar jDositions are reduced to the corresponding astronomical form of 

 right-ascensions and declinations, and thus, through the kindness of the 

 valued friend to whom both the new method and its sole results were 

 due, to connect my name in a slight degree with this great step, by 

 determining the relative positions of the principal stars in the Pleiades 

 and the Prresepe from his measures of the photographic plates. 



Just before my departure, Mr. Eutherfurd had supplied himself with 

 a yet larger telescope, adapted to the same purpose, and I improved this 

 fortunate opportunity of securing the identical photographic object glass 

 which he had employed in all his previous investigations. And when I 

 left home it was not without some ground for hoping that a sufficient 



