3'f Astronomy. — Dreadful Accident. 



a balloon of 40 or 50 feet in diameter would be necessary; 

 otherwise the loss of gas experienced by the balloon niio;ht 

 make it descend with a velocity which would endanger The 

 lives of the aeronauts. Mr. Robertson experienced this dur- 

 ing his ascent before the last, when he was in dano-er of bein"- 

 killed. 



ASTRONOMY. 



The eclipse of the sun which took place on the morning 

 of Aug. 17th was observed at- Paris, the weather being very 

 fine, by all the astronomers, Dclanibre, Messier, Bouvard, 

 Lalaude nephew, Burckhardt, and myself. I saw the com- 

 mencement at 5'' 59'" 18% at the college of France; and 

 M. Messier oijserved the cn<\ at 7'" 46'" 8". In consequence 

 of the rule I have formed to calculate such observations, the 

 same day I found the conjunction at G^ 30'" 24^ true time, 

 reduced to the meridian of the observatory. This will serve 

 as a term of comparison for finding the longitude of all those 

 countries where it may have been observed. It was annular 

 in Egypt. Delalande. 



DKEADFUI, ACCIDENT. 



On Thursday the 8th of September a steam engine em- 

 ployed to assist in clearing the works from water at the 

 tide-mills now erecting in the marsh between Greenwich 

 and Woolwich, was blown up by the force of the contained 

 fteam. The explosion was as sudden and dreadful as that 

 of a powder-mill, and was accompanied with a similar noise, 

 \\'hich was heard at a great distance from the place. The 

 engine was on Mr. Trevethiek's plan, worked by the ex- 

 pansive force of steam only, without employing condensa- 

 tion as in the engines in coiiunon use. It was literally 

 blown to pieces ; and we arc sorry to state, that by the ac- 

 cident three people were killed on the spot, and three others, 

 all that were there at the time, so much hurt that two of 

 them are not expected to recover. It was a fortunate cir- 

 cumstance that the accident happened at a ti;ne when the 

 other workmen were at dinner, or a much greater number 

 might have lost their liyes. 



Steam-engines on Mr. Trevethiek's plan require a boiler 

 of immense strength ; for they work with a power some- 

 times equal to 60 pounds on the square inch-, w hile common 

 engines, even Mr. Watts's, seldom work with more than 

 5 pounds. We are happy to state, however, that the present 

 accident arose, not from the impossibility of making aboiler 

 strong enough, but from a culpable mismanagement of a 



boy 



