Mr. Wm. Lowry oti the Combustion of Coal-Gas. SI 5 



At \5^ 1^ an irregular halo round the moon. 



Barometer in the Observatory 29'9 inches. 



Thermometer in ditto 42° 



Thermometer out of ditto 36 



Latitude 52° 5' 25". 



Perhaps some of your numerous readers may have had an 

 opportunity of witnessing the phaenomenon, and can give a 

 better account of it than the above. 



I remain, yours, &c. 



Thomas Maclear. 

 Biggleswade, Beds. March 24, 1829. 



LVI. On the Rev. W. Taylor's Experiments on the Combustion 

 of Coal-Gas, and on the best Form for Gas-burners. By 

 Mr. William Lowry, Civil Engineer. 



To the Editors of the Philosophical Magazine and Annals. 



Gentlemen, 

 T N your Number for February, I observe a notice intitled 

 *■ " New Experiments on the Combustion of Coal-Gas." The 

 experiments are certainly not new; for in the years 1823 and 

 1824, having had occasion to examine the consumption of gas 

 by different descriptions of Argand burners, 1 obtained some 

 results, which appeared at first sight paradoxical, was led 

 to vary the experiments in everj' way which seemed calculated 

 to elucidate the subject, and in the course of my inquiries met 

 with the facts mentioned in your Number alluded-to. 



Previous to giving an account of my experiments, it may be 

 necessary for those at least not intimately acquainted with the 

 subject, to state that in each of them the flame was allowed to 

 rise as high as would admit of the perfect combustion of the 

 gas, and that the results of the experiments are not com- 

 ))ared with one another, but with the light given out by a 

 quantity of gas consumed with a given height of flame by 

 burners of tlie ordinary construction. 



Burners whose circle of holes were 5-8ths of an inch in di- 

 ameter were tried with from five to fifteen holes in the circle, 

 and the consumption was always the least with the greatest 

 number of holes ; though no great difference was observed 

 when trie holes were so near each other as to allow the jets to 

 be perfectly united. 



An enlargement of the holes also produced a saving. When 

 the central air-apcrlure was stopped, or partially so, the flame 

 rose considerably, but was conical and dull ; but when the cen- 

 tral 



