GERMINATION OF SEEDS. 
131 
thirty-two feet of side flue; and a considerable advantage results 
from adopting the larger proportion for the grate and bottom surface, 
on account of the fire requiring less attention. 
The forms of boilers may he varied in a considerable degree, pro¬ 
vided the above quantity of surface receives the effect of the fire; 
the first kind used by Mr. Atkinson, was a parallele-piped with the 
fire applied to the base only. I have employed the same form, but 
of greater length in respect to its width, hence of less capacity, and 
made the flue to go round the sides of the boiler; it is then of great 
length and very effective, and this I consider the best and most sim¬ 
ple plan for an open-topped boiler, serving as a partial reservoir of 
heat. 
A boiler in the form of half a hollow cylinder, affording a great 
quantity of fire and flue surface, is made by Messrs. Bailey, (fig. 
16); and a bottle-shaped boiler (17) is made by Messrs. Cottam 
and Hallam, which has a considerable quantity of fire and flue sur¬ 
face, compared with its capacity; both these are, therefore, well 
adapted to cases where only a small reserve of heat is required for 
night. The variation of the Scotch distiller’s boiler (18) is also a 
good form for maintaining the supply of heat to the house, while a 
separate reservoir is warmed by one of the pipes. 
Another mode of obtaining a large portion of fire and flue surface 
to a small capacity, is shown in figure 20, but complicated forms 
have little to recommend them, and are expensive except when so 
small as to be cast in iron, because the fire should be partially sur¬ 
rounded by slow conductors of heat to prevent the dissipation of heat 
being too rapid, and to render the combustion of the fuel perfect, 
and, consequently effective; hence, a fire-place surrounded on three 
sides by bricks, is better than one in the middle of the boiler. 
The best mode of regulating the fire, is by means of a door to the 
ash-pit, having a register, first suggested by Dr. Black, and after¬ 
wards put in practice by Count Rumford. 
ARTICLE IV.—ON THE GERMINATION OF SEEDS. 
BY THE AUTHOR OF THE DOMESTIC GARDENERS’ MANUAL. 
In page 115 of the last Number, (March, 1835,) I observe a notice 
by “ W. M.” upon some remarks upon this subject by “ W.” which 
appear to call for a reply bv one who is prepared to enter upon the 
investigation of it, practically. I am not willing that the mere gratis 
dictum of any authority, however high it be, should pass as law, in 
