SCIENTIFIC SUMMAIIY. 
435 
of steel flat-fronted projectiles^ for penetrating armour, to the chilled cast- 
iron Palliser shot which have pointed fronts. Mr. Whitworth quoted ex- 
periments to show that when a plate was struck obliquely a flat-fronted shot 
would penetrate, whilst a pointed shot would break up and be deflected, lie 
stated that he was engaged in the construction of some guns of 11 inches 
calibre, capable of withstanding a powder charge of 90 lbs., and firing an 
11-inch shell weighing 965 lbs. and carrying a bursting charge of 45 lbs. of 
powder. — Mr. Eaton read a paper on what he terms aero-steam engines, or 
engines which work with a mixture of steam and air. The engine is fitted 
with an air-compressing pump, by which air is forced through^ a coiled 
pipe, exposed to the exhaust steam and waste furnace gases, from which it 
is delivered into the boiler, and passes with the steam to the engine cylinder. 
According to experiments at Nottingham, the evaporative efficiency of the 
boiler and the efficiency of the engine are both increased, and a considerable 
economy of fuel was obtained. Further and more varied trials will be re- 
quired to show how far this gain is due to the special circumstances of these 
particular experiments, and how far the same gain may be realised in ordi- 
nary engines of good type under the conditions of common practical work- 
ing. The invention at its present stage at least promises to be serviceable. 
— Mr. Bramwell read an interesting paper on the influence of form, consi- 
dered in relation to the strength of railway axles and other portions of 
machinery subjected to rapid alternations of strain. The paper is chiefly 
occupied by an examination of the effect of bosses and other enlargements in 
modifying the distribution of stress and the work necessary to cause fracture. 
Mesistance of Vessels . — An extremely important report, drawn up by Mr. 
Merrifield for the committee of the British Association appointed to enquire 
into the state of existing knowledge on subjects relating to the resistance 
and propulsion of vessels, was presented at the Exeter meeting. The report 
contains a complete account of the formulae and theories which have been 
proposed for estimating the resistance of vessels ; a short account of the 
principles of propellers with references to the memoirs which contain in- 
formation on the subject ; an account of the chief experiments on the resist- 
ance to the motion of floating bodies ; and an account of the theories of 
waves and of the rolling of ships. The committee suggest a series of ex- 
periments on a ship of considerable size and fine form, towed at various 
speeds, the resistance being measured by a traction dynamometer. They 
suggest that the experiments should be made in a deep and clear inland 
water, such as may be found on the coasts of Norway and Scotland. 
Fairlie’s Steam Carriage. — Mr. Eairlie’s steam carriage, or engine and 
carriage combined, has been worldng admirably at Hatcham on an experi- 
mentcvl line with curves of 50 feet radius. Thirty miles an hour is said to 
have been accomplished. The engine and carriage weigh but 13^ tons, and 
there is accommodation for 66 passengers. — Engineering, Aug. 20. 
House raising . — Many of our readers will know that in the United States 
the lifting of houses bodily and removing them to more desirable locations 
has become a regular branch of engineering. The latest feat of the kind is 
the raising of the Hotel Pelham, in Boston, a freestone building 96 feet high, 
and weighing 10,000 tons, and its removal on rollers a distance of 21 feet in 
three days. 
