= a 
334 Review of Prof. Johnson’s Report on American Coals. 
minous coals are somewhat superior to all others, and for getting 
up steam, the foreign bituminous coals take less time than either 
of the other classes. 
Has the government yet availed itself of the important inform- 
ation which these tables present, in making its purchases? Judg- 
ing from the advertisements for contracts by the navy depart- 
ment, we must say we fear not. 
Our eastern depots, we believe, except perhaps the Washing- 
ton navy yard, are supplied with anthracite for the use of steam 
ships; whilst those of the south have their supplies of the most 
bituminous character. Suppose an express shall have been re- 
ceived at one of our ports, that a pirate or suspicious looking 
cruiser has just been seen, and a steam vessel lying there shall 
be ordered to proceed immediately in quest of her. We see by 
the thirteenth column of table CC, that if every thing else is in 
preparation, it will require from three to four times as long to bring 
the steam boiler to steady evaporation by the one as the other, 
and therefore that difference in the time at which the steamer 
can be consideréd as performing its full duty. Again, we believe 
on the Mexican coast the depots are supplied exclusively with 
coals of the highest bituminous character, such as Cannelton, 
Ind. and Pittsburg, Pa. 'The results of the experiments show 
that this species of coal was admirably adapted to the short cruis- 
ing and rapid running generally required on the coast; but one of 
these vessels may be wanted to cruise among the West Indies or 
along the coast of Yucatan. From the nature of this fuel, as 
may be seen by referring to the column ‘“‘cubic feet of space re- 
quired to stow a ton,” and “pounds of steam furnished by one 
cubic foot of coal,’ it is evident that the bunkers of the ship fill- 
ed with this kind of coal would not sustain a cruise much more 
than one half as long as with some of the other coals. 
These are differences of character eminently worthy of the at- 
tention of the government. 
We merely mention these supposed cases to show the nici 
cable application of the information contained in this Report. 
Others not less important might be presented, and we hope that 
the departments of government will not fail to avail themselves 
of them. 'The money expended on these investigations has been 
well spent ;—but if those whose duty it is to apply this inform- 
ation, fail to do so, the outlay, so far as the government is con- 
