[20] Formation—a geological phrase, of German origin.
[21] Doubtless the pea ore of the Wernerians. Editor.
[22] This jet of cold water being let into the cylinder itself, necessarily cooled it at every stroke; and then it was necessary to heat it again to the boiling point, before the piston would reascend, and thus a vast loss of heat occurred. Editor.
[23] But it is not necessary (as in the plate) to crowd the engine into the after-part of the boat, the boilers maybe placed forward, and near them, or over them, the cylinder, &c. The power is then communicated to the stern-wheel by a long shaft, supported on, or immediately under, the deck. This arrangement gives room for loading both behind and before the boilers and engine, and equalizes the burden. This is the actual arrangement of the Merrimack boat.
[24] It is found with very high steam that the source of supply must be above the chamber, or a small quantity of cold water introduced to condense the steam therein.
[25] Taken from the Philosophical Magazine, and by that work from the Annales de Chimie and de Physique, for January, 1818.
[26] A method of rendering changeable the sound of the same pipes in the organ, which had occurred to the writer, but which was not inserted above on account of the supposed difficulty of making the change sufficient in degree, he has since found to have been executed by the Rev. H. Liston, who has succeeded, by means of shaders capable of being brought before the mouths of his pipes by the action of pedals, in giving them three distinct sounds each, varying by two commas. (See the description of his Enharmonic organ, in Rees' Cyc. or Tilloch's Phil. Mag.) His scale embraces 59 intervals to the octave, and is intended to produce perfect harmony in all the keys. But as it will require the use of pedals perpetually, even on the same key, and a ready and perfect knowledge of small musical intervals, which practical musicians can seldom possess, there is no probability that it will ever be extensively adopted. Perhaps, however, four or five sounds, such as D
, E