318 Economy of Fuel. 
roads, has already rivalled, if not greatly surpassed, our achieve- 
ments in steam navigation. It is however, probable that the maxi- 
mum of useful effect, has been nearly attained in both these depart- 
ments, which, when practically considered, will be found auxiliaries, 
rather than rivals, to each other. ‘The art of obtaining the full power 
of steam, and of applying it to the purpose of locomotion on a fluid 
which sustains the load and affords sufficient reaction for the mov- 
ing power, is now well understood; and in regard to railroads it is 
doubtless true, that a level metallic surface, not only sustains the veht- 
ele, in the most perfect manner, but affords the least possible resistance, 
with the best possible reaction for the propelling power, and combines, 
therefore; the greatest conceivable facilities for the transit of persons 
property.* - Other expectations, which are often entertained, 
— due consideration, will doubtless end in disappointment. — is 
the establishment and extension of these unequalled means of con- 
cies that the enterprise of our growing country should be direct- 
ed. It has been truly said that the career of improvement in our age, _ 
is too impetuous to be stayed, were it wise to attempt it, and “though 
it be a futile attempt to oppose so mighty an impulse, it may not be 
unworthy our ambition, to guide its progress, ane direct its ee 
Aur. XV.—On the Economy of Fuel with oleate to tts sdoasiill 
applications; by WauteR R. Jounson, Prof. of Mechanics and 
Datta Philosophy, in the Franklin Institute, Philadelphies es 
Tue art of heating apartments in the most economical and salute- 
ry manner, is of truly vital importance to the interests of society: 
Connected with this, the art of ventilation stands preéminent, and with 
both the art of constructing dwellings and other buildings, is intimately 
related. In all our larger towns and particularly in our maritime cities, 
the annual expenditure for fuelis enormous. New York and Philadel 
phia are believed to pay each, not less than twelve hundred or fifteen 
hundred thousand dollars per annum, for combustibles, to be ante 
ed either i in domestic uses, or in cap cama In reaper * to both 
* It may be noticed, that the power aapenes for propelling a single steam boat 
of the first class, is equal to that of fifty locomotive engines of the power twelve 
These would probably be adequate to the conveyance of all the pas 
now transported upon the the H ens 
dred to a level rail way of equal extent. 
