198 History of the Discovery of the Planet Neptune. 
moir (containing every thing which Dr. Galle had in his posses- 
sion at the time of his discovery) was presented Angust 3Ist; 
yet Galle’s ieovery was not made till Sept. 23d. What were 
the astronomers of Paris doing meanwhile? Why did they not 
both the theoretical and practical discovery, and leave to a Ger- 
man astronomer the verification of the sublimest theory of med- 
ern science? The answer is plain. ‘J'he astronomers of Paris 
did not expect to find a planet within one degree of the place 
: e expressed the opinion that its longitude would not 
be Jess than 321°, nor more than 335°. But he adds, “If the 
planet should wot be discovered within these limits, then we must 
extend our search beyond them (on recourrait aux longitudes su- 
perieures.”’) If he was sure of being able to find his planet with- 
out a long continued and laborious search, why did he not borrow 
a telescope, and at once verify his own predictions? 
or had the astronomers of the rest of Europe much higher 
faith than those of Paris. Professor Encke in announcing the 
discovery, characterizes it as “far exceeding any expectations 
which could huve been previously entertained.”’ That Professors 
Airy and Challis, although they were pretty well satisfied of the 
existence of a planet yet undiscovered, regarded its exact place in 
the heavens as extremely uncertain, is plain from their compre- 
hensive plan of observation, viz., to sweep three times over a belt 
of the heavens, 30 degrees i in length, and 10 degrees in breadth ; 
a plan which Professor Challis states it would have been impessi- 
ble for him to complete within the year 1846. 
Do we then charge Encke and wes with a want of sagacity? 
By no means. On the contrary, we maintain that they had no 
reason to expect to find the planet within one degree of the com- 
puled place. Le Verrier’s own statement of the limits within 
which the planet should be sought for, is sufficient proof of this. 
But we go further. Le Verrier | thought his problem was capable 
of but one solution; that is, that there was only one point of the 
heavens in which the disturbing planet could be placed so as to 
acconnt for the motions of Uranus. [un this (according to Profes- 
sor Peirce’s computations) he was mistaken. Professor Peirce an- 
nounced in April, 1847, that he had discovered two other solutions, 
which are decidedly different from each other, and from that of 
Le ae, and equally complete with his. Moreover, Le Verri- 
er ascribed the whole effect in question to one planet ; ‘while it is 
almost certain (we are half inclined to omit the a/most) that more 
than y is concerned | in producing the effect. fessor 
sagacious, as well as brave gen- 
