LIST OF ILLUSTRATIONS ON WOOD, xxix 



FIG. PAOK 



325. Steam-roller - 483 



326. Aveling and Porter's steam ploughing-engine 485 



327. Direct system of steam ploughing 486 



328. Steam block-rammer : section of the cylinder 489 



329. A steam block -hammer 490 



330. The latest form of the Walter press 492 



331. Section of the cylinders in Laubereau's engine 507 



332. Laubereau's hot-air engine 508 



333. Lenoir's gas-engine 510 



334. Decimation compass 521 



335. Gambey's declination compass 522 



336. Ship's, or mariner's, compass 523 



337. The binnacle of a man -of- war 524 



338. Variation compass 525 



339. Portable declination compass 525 



340. Surveying compass 526 



341. Dip circle 528 



342. Conical point of red copper in the lightning-conductor 537 



343. Vertical rod of the lightning-conductor 537 



344. Junction of the vertical rod to the conductor 538 



345. The fixing of lightning-conductors. Vertical and oblique rods . . . 539 



346. Limits of protection of a system of lightning-conductors fixed on a 



building 540 



347. Lightning-conductor with multiple points .... 541 



348. Electro-magnets 547 



349. Wheatstone's five-needle telegraph 549 



350. Cooke and Wheatstone's single-needle telegraph manipulator and 



indicator 550 



351. Belgian and English vocabularies of the single-needle telegraph . . . 551 



352. Two-needle telegraph 553 



353. Vocabulary of the two needle telegraph 554 



354. Bain's I and V telegraph, 1843 555 



355. Henley and Foster's magneto telegraph, 1848 : indicator movement . . 556 



356. Indicator of needle telegraph, Foy and Breguet's system 556 



357. Manipulator of Foy and Breguet's needle telegraph 557 



358. Vocabulary of Foy and Breguet's needle telegraph 558 



359. Manipulator of Breguet's dial telegraph, new form 559 



360. Breguet's manipulator, old form 560 



361. Indicator of Breguet's dial telegraph, external view 562 



362. Breguet's indicator, view of the mechanism 563 



363. Details of the mechanism in Breguet's indicator 564 



364. A dial-telegraph station 566 



365. Wheatstone's letter-showing dial telegraph, 1840 568 



366. Nott and Gamble's letter-telegraph, 1846 569 



367. Siemens' and Halske's dial telegraph 569 



368. Manipulator of Siemens' and Halske's dial telegraph 570 



369. Indicator of Siemens' and Halske's telegraph 571 



370. Froment's dial telegraph : manipulator 572 



