PHOGRKSS OK ASTKONuMY FOR 1891 AND l,si)2. (iOf) 



Paris. — Iiistniiiic'iil rciitly . 



I'ohiduiH. — Instruiueut ready ;iiul a imiiilxr of jilalis suliiiiil Icil tn ilic iu.sptM-l ion of 

 the couiuiittct'. 



liio de Janeiro. — The photoj;iiipliic eiiiiatoiial has licuii iiMeivcd ami will he 

 uiouiited at the new site of the ol)S( r\ atoi y. 



Home ( I'iitiedti). — 'I'lic iustruuHMit has Ucrn i<>iiii)l«?tfil. 



San Fernando. — The iiistruinciits arc iiiouiitcd and wink can lie I)«'l;iiii as sunn as 

 thereseau is HM'ei\t'd. 



Santiago. — Tlit; iiistrmiR'ut is liiiished. hiil, uwiiiu (o ixditical distiirliamc in Chile 

 it is impossible to tix ;i day for bc.uiuuins' the work. 



Si/dnei/. — Ready exeept for the " re,s(aii." 



Tacithajia. — Instrument ready aud a number of experimental i)lates submitted. 



Tonlonsc. — The instrument was one of the first to be mounted; the '• rvsemi " and 

 photo.n'raphic plates a.re only needed to begin the, work. 



Following is a sumin:iiy of the resolutions adopted at this lueetino-: 



(1) jSo change is made in tin' conditions of distance and magnitude 

 of the stars that have formed the diffeieut parts of the catalogue ol 

 guide stars. 



If, however, the guide star of the catalogue is not bright enough, a 

 brighter one maybe selected up to a distanc<' of 10' from tlie c<'nrer 

 of the plate. 



(2) The ^'■rr.scan"' is to be i)hotogra]ihed upon each i>late l)y \)araliel 

 raj's of light. (To rei)lace resolution lo adoi)ied at the meetiug of ISS',).) 



(3) The orientation of the }>lates iu zones above do- declinatiou will 

 be arranged for the ecpiinox of VMH)-. for othei- stars the jtaiallel will 

 be referred to the api)arent ecptinox. 



(4) Tlie woik decided upon by the congress of 1SS7 comi)rises two 

 series of negatives made with different exi)osuies. The committee, 

 while urging" special activity in securing {dates of shorter exjxtsure 

 (negatives intended for the catalogue), would suggest that the best 

 nights be also taken advantage of for plates of l(»nger ex])osurc (for 

 the chart). 



(5) Negatives from which the catalogue is to be formed will have 

 two exposures for the same plate, one showing faintly the images of 

 stars of the elev'enth magnitude, the other with an exposure twice as 

 hnig, the distance of the two images being 0.1* to ().;; of a millimeter. 

 (To replace resolution Uo of the meeting of ISSt).) 



(6) MM. Abney aud ('ornu are added to the coiinnittcc on reiuoibic- 

 tiou of the negatives, 



(7) With reference to the prodiu-tion of the chart, purel\ piu>to- 

 graphic methods will be used, to the exclusion of all manual interven- 

 tion. 



(8) For the chart proi)er (long exposures) a series of negatives witii 

 single exposure will be taken, having an cvf}! degree of declination iu 

 the center of the ]»late. Further stud.x will show whether it is desir- 



