Miscellaneous Intelligence. _ | 285 
Upon an anvil, a disk of paper, three inches in diameter, was laid 
covered with pulverized sugar. Over the sugar was placed another 
similar disk covered with pulverized nitre. A bar of iron, rather wider 
than the disks at a welding heat, was then held over them, and sub- 
‘jected toa — from a sas An explosion, with a report like that 
of a cannon, ensued. * 
Instructed we the facts and considerations above stated, it is inferred 
that the explosions which contributed to extend the conflagration in 
ew York, as Gitaipiasgit, arose from the reaction of the nitre 
is presumed that as soon as the fire reached any of the gunny bags, it 
must have run rapidly through the whole. pile, by means of the inter- 
Stices necessarily existing between them, the nitre with which they 
were embued causing them to deflagrate. Much of the salt being thus 
brought to the temperature of fusion, it must have run about the | floor, 
reached the combustibles, and soon found its way to the next story 
through the seuttles which were open. All the floors must have been 
activity any ordinary’ combustion. Meanwhile, the nitre being all 
liquified and collected in the cellar in a state of incandescence, and 
aided by the molasses, the weight, the liquidity, and menue ig must 
have pied all the conditions requisite to intense detonation 
floors having been consumed, the store must have been. squivilaat to 
an enormous crucible of twenty feet by ninety,at the bottom of whic 
were nearly three hundred thousand pounds of nitre, superficially heat- 
a million of pounds. The intense reaction, however, would not per- 
mit of durable contact. Ateach impact, the whole mass ani have 
been thrown up explosively, and hence the successive detonations. 
But the chemical reaction, the heat, and the height of the fall, growing 
with their growth, and strengthening with their strength, the last ele- 
vation was succeeded by the pea report and stupendous ex- 
tesa of reas it has been an object to afford a satisfactory expla- 
nation 
3. iding Material—The following are the results of examina- 
tions byt ths building committee of the Smithsonian Institution, of dif- 
ferent kinds of building material in Maryland, as mentioned in the re- 
cant Report of the Regen 
“Ist. That the marble quarries of Maryland, chiefly in the vicinity of 
the village of Clarksville, about thirteen miles from Baltimore, on th 
line of the Susquehanna — contain. two qualities of anrhie: one 
* In a short time a more circumstantial account of ai Hare’s tacts and 
inferences respecting the subjects of the above commuhication will be published. 
_Sxconp Senrtzs, Vol. VI, No. 17.—Sept., 1848. 37 
