534 Chronicles of Science. [Oct., 



superior to what has previously been introduced, as to warrant some 

 prominence being given to the subject. Some years ago a steam- 

 engine used in an industrial establishment at Muhlhouse in France, 

 was converted into an aero-steam engine by the simple addition of 

 a pump to force air into the boiler ; a considerable increase of power 

 was stated to have been thereby secured, but its success does not 

 seem to have continued long, and the experiment did not then 

 secure much general favour. Kecently, however, the subject has 

 been revived, and two inventors claim the support of the public on 

 behalf of their respective inventions. The first of these is Parker's 

 steam and air engine, and the second Warsop's aero-steam engine ; 

 the general principles involved in each are the same up to a certain 

 point, but the methods of applying them differ considerably. In 

 Parker's engine the air is drawn directly into the steam-pipe, lead- 

 ing from the boiler to the engine, by means of the force of the 

 steam passing through it; this steam-pipe is sometimes passed 

 through a small coke fire, in order to raise the temperature of the 

 united steam and air, but this is not considered in any way essential 

 to the utility of the apparatus. Experiments made with it are 

 reported to have resulted in considerable economy of fuel combined 

 with increased efficiency of engine power. 



Warsop's aero-steam engine consists in the use of an air-pump, 

 worked either by the steam-engine itself, or by a donkey-engine ; 

 this pump takes in cold air which, after being compressed, is forced 

 on through an air-pipe passing through the smoke-box, or some 

 other part of the boiler where heat can be taken up from contact 

 with the waste gases. The highly-heated air passes a self-acting 

 clack-valve into the bottom of the boiling water, and is so distributed 

 by simple mechanical means, that it rises constantly through the 

 water. On rising above, the air is saturated by the steam, and 

 the two together pass on to their duty in the cylinder. From a 

 series of experiments carried out with this engine at Nottingham, 

 it appears that in the amount of useful work done for fuel expended, 

 the advantage rested with the combined steam and air system, as 

 compared with when steam only was employed. 



Thames Embankment. — Upwards of eight years have now 

 elapsed since the reclamation of the foreshore of the Thames between 

 Westminster and Blackfriars Bridges was undertaken by the Metro- 

 politan Board of Works. This magnificent boulevard was opened 

 on 13th of July last. It consists of a roadway 100 feet in width 

 throughout, having on the river-side a foot pavement 20 feet wide, 

 and on the opposite side one of 16 feet; the former is edged by a 

 row of trees, planted at intervals of 20 feet. The total amount of 

 land reclaimed is 37£ acres, of which the carriage-road and footways 

 occupy 19 ; 8 acres will be converted into ornamental gardens for 

 the public use, and the remaining 10^ acres pass over to the original 



