EIBLIOGKAniY OV HKUSCIIKI.'s WRITINGS. ;>''^0 



Herschel, W.: SvNorsis of tuk W.miNOs oF-C.nlinno.l. 



A.D. Vol. P. . , . *• 



1800 9G 215 Table X contains llu" result of calnihitioii .It the I'-'nnanent .luauti- 



ties. It has six columns: (1) gives the star's name; (-2) its pro- 

 portional distaucc ; C.J) apparent motion ; (4) Direction vritb tho 

 parallel; (5) Direction with the parallactic motion; (C) Velocity. 

 [There are 3G stars. ] 



216 Plate IV, Fig. 1 and Fig. 3, exhibits columns 3, 1, and r. graphically. 



Fig. 2 and Fig. 4 give the velocities. 



217 liernlrks on the sidereal Motions as they are represented from Observation. 

 Fi^. 1 (from observation) shows that there must bo some physical 



cause which gives a bias to tho directions in which the stars are 



moving. Discussion of Figs. 2, 3, 4. 

 219 The Solar Motion and its direction assigned in the first part of this paper 



are confirmed by the rhenomena attending the observed motions of 3G stars. 

 • 221 Trial of the method to obtain the Quantity of the Solar Motion by its Bank 



among the sidereal Velocities. 

 22--> Calculations for investigating the Consequences arising from any proposed 



Ouantity of Solar Motion and for delineating them by proper Figures. 

 2-->3 Table XI contains 5 columns: (1) name of star, including the sun ; 



(2) Parallactic Motion; (3) Real Motion; (4) Parallactic Angle; 



(5) Velocity. 

 224 Fio-s. 5 and C illustrate Table XI. 



224 EemarU that lead to a necessary examination of the Cause of the sidnral 



225 A motimrof the stars may arise from mutual gravitation or froni an 



original projectile force. Both these causes act m the solar system. 



oor, The similar direction of the motion of a group of stars may be as- 

 cribed to their similar projectile motions. r- , ■< e 



227 Consideraiions of the attractive Power reguircd for a sufficient T elo.ity of 

 ihc sidereal Motions. , 



The mere attraction of neighboring stars «-t\ug upon eac c^^^^^^ 

 cannot he the cause of proper motions, f^^^^^^^^^'^^l^^ IZ 

 that cause would approach yearly by less than .OOOOOOOOo to 

 eye at the distance of Sirius and supposing its r=^^-^Uax 1 • 



228 A centre of attraction must then he assumed, and original pro,, ctile 



229 motions must be supposed. 



ooo Tbfl centre of attraction may bo one mass or a group. 



IS SrttmX a union of groups; like two Cn.t.rs n' a„an .mcU 

 are near the line of the 8olai> motion. 



o*?! The Milkv Way will furnish centres of attraction. 



Si IndeJendenTof the solar motion, the action of distant centres of 



''' 'IractnwiUhe required to explain the proper motions of^s^^^^^^^^ 

 If the Sun he at rest Arctnrus moves 2" a year; an^l ^lu. must be 

 dL to a projectile motion and the attraction of far distant center 



232 I^2:Lif the Quantity of the solar Motion. ^^^^-;^^ 

 to the solar motion is a perfect luedium among the [ob] 

 velocities fwhich have been considered.] ,^;„vt 



annually 1". 116992. . , , -, 



234 Concludin nemarlsand Inferences. [Objections consi.lcrcd^] 



SI mena/eneral knowledge of the I'^/- ^e. it Xt cal- 

 tho 1st, 2d, and 3d magnitudes has been obtaine.i, in i 

 culation can be repeated-by the same methods. 



