A412 W., A. Norton on E’ricsson’s Caloric Engine. 
With her present capabilities the average speed of the Ericsson 
at sea would not exceed 6 miles per hour (see Journal of the 
Franklin Institute for February, No. 2, p. 127); and she would 
require 24 days to perform the voyage to Liverpool (3550 statute 
miles). It seems highly probable that her speed will be increased 
by alterations and improvements in her machinery, but it is to be 
observed that when depressed to her load-line, the full estimated 
power of her engines will propel her at no more rapid rate than 
84 miles per hour, in still water, and less than 7 miles per hour 
at sea. 
6. Application to Inland Navigation, &c. 
The weight of the caloric engine, and the large amount of 
space which it requires, would seem to preclude all hope of ap- 
plying it successfully, in its present form, to river or lake naviga- 
tion or to railroad locomotion. (See table on p. 408.) In its 
application to manufacturing purposes and to the drains of mines, 
¢., the same objections will have much less force, and a favora- 
ble result may therefore be more confidently expected. In this 
point of view, however, a comparison should be instituted be- 
tween the caloric engine, and the high pressure steam engine 
working very expansively. 
General Conclusions. 
The more important general conclusions to which this com- 
parison has conducted are, 
1. That Ericsson’s Hot Air engine, as compared with the con- 
densing marine steam engine in its most economical operation, 
has shown the ability to do the same work with the use of from 
3 to $ less fuel; and that if its full estimated power should here- 
after be developed, the saving effected would be 70 per cent. 
_%. That, for the same actual power its weight is about three 
times as great as that of the marine steam engine, and that in 
case its estimated power should be obtained, its weight would be 
a8 much as 30 per cent. greater. ' d 
8, That, in respect to the space occupied by the engines an 
coal, the advantage is decidedly in favor of the steam engine. 
A. That, the great weight of the engine in proportion to “ 
power developed, must prevent, for the present, the realization © 
Shieh speed in the propulsion of vessels, At the same time it 
18 to be admitted that the full estimated power is adequate to ro 
reduction of high velocities. Time alone can decide the ques~ 
tion whether or not this maximum power is really obtainable. ‘ 
RS ‘The 8reat weight of the engine, and the space occupied | Y 
it In its present form, will in all probability prevent its adoption 
for the purposes of inland navigation and railroad locomotion, 
in preference to the steam engine. If used asa land engin@, 
