These are some of the principal applications of the steam engine ; but the most important of all is its ap plication to Carriages and vessels, which is treated of in the separate Articles STEArn-BoAT and STEAM CARRIAGE. For farther information on the subject of this section, see Tredgold on the sect. ix.
As the preceding article is intended only for the pe rusal of general readers, those who wish to prosecute the subject farther may consult the following works:— Switzer's System of hydrostatics; llelidor's 3rchi tecture Hydraulique ; Desagulier's Experimental Phi losophy; Ferguson's Lectures on Mechanics, vol. i. p. 312 Smeaton's Reports; Prony's Nouv. Architecture Hydr ' aulique; Robison's Ilkehanical Philosophy!, vol. ii.; Ilisiory of the Steam Engine, Lond. 1824 ; Montgery's Notice Ilistorique sur _In vention des illachine-a-l'apeur ; Farey's Treatise on the Steam Engine, Historical, Practical, and Descriptive, Lond. 1827 ; Partington's Historical and Practical Ac count of the Steam Engine; Tredgolcl's Steam. Engine, Lond. 1827; Lardncr's Popular Lectures on the Steam Engine, Loud. 1828 ; Birkbeck and Aldcock on the Stearn Engine.
An account of the most recent improvements on the steam engine, as made in Cornwall by Mr. Henwood, will be found in Dr. Brewster's Journal of Science, No. XVIII. and No. XIX.
It is not only agreeable to know the gradual progress which all arts, sciences, and improvements have made, from the first rude attempts to perfection ; but proper, in a work of this kind, to detail them. The author of the preceding article makes no mention of Hero of Alexandria, or of Porta the Italian, both of whom may be said to have invented steam engines, or at least to have demonstrated the elastic force and moving power of steam. The first lived about 130 years before the Christian era ; and in his work entitled Spirilalia, describes a machine to which motion is to be given by the force of steam. It consisted of a hollow globe, having tubular arms ex tending in opposite directions, and having openings at different sides near their extremities. The globe was suspended upon centres, fixed upon pillars, one of which and one of the centres was hollow. Steam
was introduced from a cauldron, and issuing through the hollow column and centre into the globe, passed through the arms into the open air, producing a rotary motion.
• In the year 1560, Alathesius, a German, suggested the practicability of a plan by which steam could be employed. In Leipsic, a machine upon a similar plan to that of Hero was proposed to be substituted for the turnspit-dog, then in use.
Porta, a Neapolitan, published the account of his apparatus in 1606, in an Italian translation of Hero's work. The boiler a has a long neck, which passes through the bottom of the close cistern b, containing water. A bent pipe or syphon e is closely fitted into the top of the cistern, and descends nearly to the bottom. When the fire is lighted under a, the steam ascends into the cistern, presses upon the water, and forces it up the syphon c, whence it runs in a stream.
Mr. Ainger observes that this was an extraor dinary suggestion, and it is surprising that the project was not sooner reduced to practice, than is found to he the case.
The contrivance is a great improvement on that of Hero (who pro posed to use solar heat), because the steam from heated water in one ves sel is made to drive up cold water from another vessel, instead of driving up the heated water from which the steam is pro duced. With this important modification, the ap paratus resembles that of the Marquis of Worcester, in 1663, excepting only in the extent of its power.
In the year 1615, according to M. Arago, De Caus, a native of Normandy, published at Frankfort a work entitled Les Raisons des forces mouvanles avec diverses Machines /ant utiles que plaisantes,* &c., and dedicated it to Louis the X11I. The fifth theorem is thus headed: L'eau montcra par aide du foul plus haul qiie son nireau and the explanation of this with a diagram exhibits a real steam engine, capable of producing a vacuum. This was forty-eight years prior to the appearance of the Marquis of Worcester's Century of Inventions, which was Nv ritt en in 1655, and first ap peared in print in 1663.