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Philosophical, Chemical, and Scientifc Miscellanies. [June, 



tity than the tenth or twelfth part of a 

 second of tune. Mr. W. Hardy, whose 

 ingenious escapement in particular, and 

 many other improvements in the construc- 

 tion of chronometers, have frequently at- 

 tracted the notice and obtained the com- 

 mendation of scientific men, has recently 

 brought to perfection an ingenious machine, 

 on which the name of ' Akaremeter ' has 

 been bestowed, by which he purposed to 

 ascertain still smaller portions -of time. 

 While the second hand of this instrument 

 describes the fifth part of a second, a smaller 

 hand attached to the balance axle traverses 

 an arc divided into 120 parts, each of which 

 consequently is the six-hundredth part of a 

 second. The action of the machine com- 

 mences and ceases by pressure upon a stud. 

 The degree of accuracy with which any 

 interval of time might be determined was 

 now to be ascertained ; and after allowing 

 for the error in transmitting the will, and 

 for that arising from the divisions on the 

 small arc being equal, when the motion of 

 the hand is alternately accelerated and re- 

 tarded, it seems probable, from many ex- 

 periments which liave been made by Mr. 

 Babbage and the Rev. T. Hussey, that the 

 instrument may be depended upon to the 

 thirtieth, or at least to the twentieth part 

 of a second of time, an approximation 

 which will scarcely be siu-passed, except by 

 the introduction of a conical pendulum. 



Perkins's Steam Eiii/inc — Mr. Perkins's 

 system of generating high steam has re- 

 cently been applied to the Comish single- 

 stroke pumping engine, and the Messrs. 

 Hornblower have made the following re- 

 port on its effects : " Its great power is 

 established by the fact of its having lifted a 

 column of water 40 feet high, and 40 inches 

 diameter, with a 9'.33-inch piston. As to 

 the economy of fuel, which is evidently 

 great, we cannot exactly say, owing to 

 some parts of the engine being incomplete, 

 especially the injection pump. The longest 

 the engine has worked at any one time was 

 two hours ; at that time it was making 

 14 strokes per minute, 65 feet strokes, 

 and lifting a column of water 36 feet high 

 and 40 inches diameter, consuming not 

 more than 100 pounds of coal per hour. 

 We also certify that Mr. Perkins's flexible 

 steel piston is quite light, although at times 

 working at a ])ressure of 50 atmospheres." 

 The highest Mr. Perkins has ever used his 

 steam for his steam engines, is 800 pounds 

 to the inch, or about 57 atmospheres. 

 That the gain goes on in a geometrical ratio, 

 his experiments on the steam gun have 

 fully demonstrated : in some of these, a 

 pressure of 1,000 pounds to the square 

 inch has been used with perfect safety, and 

 was found to propel musket-balls of the 

 same weight and at the same distance, one- 

 quarter farther into the target than the 

 strongest gunpowder. In the " Discourse 

 on the Progress of the Arts, Sciences, and 

 Literature," which was delivered by the 



Institute of France to Napoleon, in Fe- 

 bruary 1808, very honourable mention is 

 made of a machine, approved by tlie class 

 of the sciences, the Pyreolophorus of 

 Messrs. Lenieps, a new invention, in 

 which, if we understand the very short no- 

 tice concerning it which the Dutch editor 

 of this report has given in a note, the force 

 of air or vapour suddenly expanded by heat, 

 is made to raise a weight or overcome a re- 

 sistance. In an experiment made with 

 this machine, it is said that a boat, loaded 

 with five quintals, and presenting to the 

 water a prow of the area of six square feet 

 was carried up the Loire with a velocity 

 double that of the stream. In anotlier 

 experiment, the pressure exerted on a 

 piston of three square inches was in equi- 

 librio with 21 ounces, and the fuel con- 

 sumed weighed only six grains. We want 

 here a necessary element, the time in 

 which these six grains were consumed. 

 This omission may perhaps be supplied 

 from another part of the account, where it 

 appears that each stroke of the piston 

 takes up five seconds ; the six grains were 

 the fuel consumed in six seconds. In 

 comparing the principle of this machine, 

 imperfect as is the account of it we have 

 been able to obtain, with that of Mr. Per- 

 kins's engine, we are tempted to say witli 

 a very able correspondent of M. Schuma- 

 cher, " there is notliing new under the sun. " I 



Mcastaes. — " La metre est la dix mil- 

 lioneme partie de la distance du pole a 

 I'eqiiateur, comptee sur le meridien qui 

 passe a Paris." La Croix. — The absurdity 

 of assuming as the basis of all measures of 

 length a quantity which cannot be assigned 

 correctly, has long been recognized by 

 every nation but tha one in which it ori- 

 ginated. The English have been more 

 precise in their choice of an unit ; an inch 

 may be defined the one 39'1384-2d part of the 

 length of a penduhim vibrating seconds at 

 the level of tlie sea, in latitude 51° 31' 8-4" 

 N. and at the temperature of 62° Fahren- 

 heit. Has Captain Kater, to whose la- 

 borious ingenuity, displayed at much ex- 

 pence to himself, this country is indebted, 

 not for the blundering arrangement of the 

 new scale of weights and measiu'es, but for 

 the accurate adjustment of the standard 

 when selected by others, derived any be- 

 nefit from his exertions, or even just re- 

 muneration for his services ; or is it thought 

 that merit, like virtue, having the privilege 

 of being its own reward, would be highly 

 unreasonable in aspiring to any other ? 



Ma7i. — M. Bory de Saint Vincent has 

 published a new arrangement, with a new 

 nomenclature of the species of the human 

 race, viz. 1. Japetic; 2, Arabic; 3, Hin- 

 doo; 4, Scjlhian ; 5, Sinic (Chinese); 

 6, Hyperborean ; 7, Neptunian ; 8, Aus- 

 tralasian ; 9, Columbian ; 10, American ; 

 11, Patagonian ; 12, Ethiopian; 13, 

 Caffre; 14, Melanienne (Black) ; 15, Hot- 

 tentot. From these fifteen grand divisions. 



