134 



To the Editor of the Analyst. 

 Sir, 



As the long-expected Comet of Halley is now actually visible, 

 and many of your readers are, no doubt, anxiously anticipating the 

 pleasure of watching its phenomena, I have thought that it might 

 not be unseasonable to lay before them, through the medium of 

 your Journal, a few notices as to the best method of making such 

 observations upon it as may be of real value and interest. The ge- 

 neral diffusion of scientific attainments would appear, at first sight, 

 to render this a superfluous task ; but I am convinced that the scar- 

 city of accurate information respecting Comets, is much greater than 

 is usually supposed: most of the popular statements, even down 

 to the present time, being either very defective or shamefully erro- 

 neous ; while such as are sufficiently explicit, and deserving of confi- 

 dence, are not very accessible. J. have therefore compiled, from un- 

 questionably authentic sources, an enumeration of the phenomena 

 whose existence it will be desirable to ascertain by observation in 

 the present case. If any of your astronomical readers should find it 

 serviceable in drawing their attention to the points most deserving 

 of notice, I hope that, with your sanction, they may be induced to 

 communicate their observations to your periodical ; which, if all 

 made upon system, and with an uniform view to determine the pre- 

 sence or absence of certain phenomena, would not fail to possess 

 great interest individually, and collectively, no small value and im- 

 portance. 



I remain. Sir, your humble servant, 



THOMAS WILLIAM WEBB. 



T retire y near Ross, Sept. 16, 1835. 



HINTS TO OBSERVERS OF HALLEY's COMET. 



It is well known to thosa who are in the habit of using telescopes, how 

 little can be seen, in many cases, bv a person whose eye is entirely unaccus- 

 tomed to the object to be observed, and who has no previous notion of the 

 particulars to which his attention should be more expressly directed. This, 

 of course, will be peculiarly the case with an object so faint and undetermined 

 as a Gomet; and it is by no means improbable that, unless observers previ- 

 ousl}"- determine upon the points which require attentiv^e examination, the 

 Comet may pass repeatedly through the field of their telescope, without 

 their being aware of the existence of phenomena which, taken in connection 

 with older observations, may prove of considerable importance. We know 

 so little as yet of the real nature and construction of these wonderful bodies, 

 that we cannot presume to advance to anything like a generalization of the 

 observations hitherto made, many of which would appear to be contradictory 

 and inexplicable : we must therefore, at present, be content with accumulat- 

 ing as many well-authenticated facts as possible, deduced from a careful exa- 

 mination of every Comet that visits our system, from a combination of 

 which we may, at some future period, be better able to develope the laws that 

 govern their mysterious construction. The subjoined particulars appear to 

 jPe very worthy of attention with this view ; and they are humbly offered to 



