General Notices. 



29 



on the bottom of the boiler, the more effective it will be. Under such 

 impressions, I have turned my particular attention to that form of boDer 

 which is most likely to answer the required end; and I have lately 

 had them constructed to the patterns shown in figs. 2, 3, 4, and 3. 



General plan of bars and flue ; the dotted line b is the supposed position of the lower pipe ■ the 

 dotted line c is a pipe for drawing off the water from the boiler and pipe. ' 



and I have found them to answer beyond my most sanguine expectations. 

 1 have found that the required heat for a house has been raised in much 

 less time, and with less fuel, than with the square or circular boiler ; for 

 although 1"2 lb. of coals will boil a cubic foot of water, in a vessel properly 



constructed for that pur- 

 pose, yet such a nice cal- 

 culation is not suitable for 

 a hot-water apparatus. For 

 instance, the proprietor 

 would sometimes burn coal, 

 sometimes coke or wood, 

 or perhaps only cinders; 

 therefore, the more econo- 

 mical the furnace is con- 

 structed for such purposes, 

 the better. The dip shown 

 at the end of the boiler 

 ( fig. 2. a) has a tendency 

 to prevent the flame from 

 passing so rapidly over the 

 bottom as it would do on 

 a straight bottom. The 

 upper part of the flue 

 passing round the boiler, 

 is entirely covered by the 

 upper part of the boiler; 

 and I always bear in mind 

 to let the lower pipe enter 

 the boiler where it is least 

 exposed to heat. I am, 

 Sir, &c. — D. D. Neeve. 

 6. Wyndham Street, Bryan- 

 stone Square, Sept. 1831. 

 Elevation of furnace. 



