Mr. Davies Gilbert on the Luminous Belt of Sept. 29. 453 



actuated by motives and principles as pure as his own. In- 

 temperate attacks, such as this, reflect back upon their author, 

 and indicate a mind inflamed by pique, jealousy, or some un- 

 worthy passion. We know not whether any cause for such 

 feelings may exist in the present case, nor does it concern us 

 to inquire ; but we know Dr. Thomson to be devotedly at- 

 tached to his profession, and we believe him to be sincere and 

 honourable in his transactions. If deception exists at all, we 

 are satisfied that Dr. Thomson himself is more deceived than 

 any one. It is possible that, misled by a favourite hypothesis, 

 he may, like many before him, have been too eager in seizing 

 facts favourable to his views, and too tardy in perceiving those 

 that are unfavourable. On this we offer no opinion at pre- 

 sent ; but must confess that several circumstances concur in 

 shaking that confidence in the accuracy of his results which 

 we once entertained. Dr. Thomson must be aware that the 

 composition of the chloride of barium, as stated by him, has 

 been declared byBerzelius to be erroneous ; and that this error, 

 if such, will vitiate many of his analyses. Would it not be 

 prudent in Dr. Thomson to come forward and correct any 

 mistake which he may have committed, rather than by delay 

 allow others to do so for him ? Does not the deference which 

 British chemists have of late paid to him in adopting his 

 atomic weights, impose on him the duty of admission or de- 

 fence ? 



LXXIV. On the Luminous Belt of September the 29th. 



To Mr. Richard Taylor. 

 Sir, 



1THE luminous belt which exhibited itself on the evening of 

 September the 29th, in the present year, having been 

 noticed and described from various parts of England, I beg 

 leave to communicate its position as observed at a point very 

 distant from most of the other stations, and therefore likely to 

 be affected by a considerable parallax. 



I was then at llosemorran, the seat of George John, Esq., 

 an elevated situation near Penzance, and about twelve miles 

 from the Land's End. My attention was called to this unusual 

 phamomenon at about eight o'clock. The belt then appeared 

 to rise from the horizon, somewhat to the southward of west, 

 and ascended with a steady light and uniform subtense, of 

 perhaps three degrees, towards the zenith, passing over various 

 stars that were scarcely altered in their appearance, till it 

 reached Alpha Lyra?, then somewhat south of west, and nearly 



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