Ml.( If A VICS. 



127 





EXERGUE 7. 



1. II man-tel-lo dcl-lo zi-o. 2. L' a-bi-to di Gio-van-ni 3. 

 La ca-sa di mi-a so T rol-la. 4. I14e-var, il tra-mon-tar del so-le. 

 5. II no-me di Gius-to, di - Gran-de. 6. La-na di pe-co-ra. 

 7. Pun-to di vi-sta. 8. La ctt-sa- di cor-re-zid-no. 9. Sen-te-si 

 un cdl-po di pis-to-la. 10. Ca-vo di pie-tra o di mar-mo. 11. II 

 su-o ca-pod' 6-pe-ra. 12. II cor-i>o di guar-dia. 13. Con un sol 

 trat-to di pen-na. 14. Un tdc-co di cam-pa-na. 15. Ve-tro di 

 fi-nfi-stra. 16. Fior di-lat-te. 17. U'-na ghir-lan-da di fid-ri. 

 18. Pez-zo d' i-gno-ran-te che sei ! 19. La piin-ta di col-tel-lo. 

 20. U'-na ve-na d' ar-gen-to. 21. Do-ma-ni o gidr-no di p6-sta. 

 22. Ma-e-stro di di-ac-gno, di scher-ma. 23. Tri-bu-na-le d' 

 Ap-pel-lo. 24. Bi-gliettto di Idt-to, del mdn-te. 25. La po-sta 

 di ca-val-li. 26. Cer-ti-fi-oii-to d' uf-fi-cio. 27. Im-pe-ro d' 

 Au-stria. 28. Bo-gno d' In-ghil-ter-m, di Sc6-zia, d' Ir-lan-da. 



29. La oit-ta di L6n-dra, d' E-din-biir-go, di Dub-li-no, di Man- 

 ce-stria, di Li-ver-pu-la, di Bir-min-ghe-mio, di Gla-sc6-via. 



30. II- m-se di Gen-na-jo, di Mag-gio. 31. II nd-mo di Giu- 

 slp-pe, di Fran-ce-sco. 32. L' i-so-la di Si-ci-lia, di Sar-de-gna. 

 33. Un quar-to d' d-ra. 34. U'-na niz-za di ca-ui. 35. Cdr-sa di 

 ca-Val-li. 36. Le trup-pe di pre-si-dio, di guar-ni-gid-no. 37. La 



. ra-da di Trie-ate. 38. II di-rit-to di ton-nel-lag-gio. 39. Taa-sa 

 di bdl-lo. 40. Un giuo-GO di ca.r-te. 41. l'iu-mo di struz-zo. 

 42. L' ac-con-cia-tu-ra del ca-po. 43. L' <5r-di-ne del gidr-no. 

 44. Die-ci brac-cia di te-la, di pan-no. 45. Un ba-ri-le d' 6-glio, 

 di a-ce-to. 46. U'-na lib-bra di.ci|r-ne, di for-mag-gio. 47. U'n 

 cen-ti-na-jo di zuc-che-ro, di caf-ft>. 48. Un m6g-gio di grii-no. 

 49. Un pez-zo di pa-no, un t6c-co. d' ar-rd-sto. 50. U'n qukr-to 

 di bn-tir-ro. 51. Un bio-chie-ro di vf-no, di bir-ra, 52. H6 

 com-pra-to die-ci bot-ti-glie di Bor-g6-gna o sei di Sciam-pa-gna, 

 53. U'-na cas-sa di pi-pe. 54. U'n gran nu-me-ro di lu-pi. 

 55. U'-na quan-ti-ta di p6-co-re, di man-zi. 56. U'-na in-fi-ni-ti 

 di gen-te. 57. U'n pa-jo di scar-po vec-chio. 58. Du-e p:i-ja di 

 ti-va-li, cu cal-zd-ni, di cal-ze. 59. U'-na ven-ti-na di zec-chi-ni. 

 60. Cin-que mi-glia di stra-da. 61. U'-na ohfc-cho-ra di caf-fe. 

 62. U'-na taz-za di te. 63. U'-na prc-sa di ta-bac-co. 64. Pren- 

 de-te-mi la mi-su-ra d' un cap-p6t-to e d' uu pa-jo di cal-zd-ni. 

 65. U'-na mii-ta di ca-v41-li. 



MOTION OF FALLING BODIES. 



WE are now in a position to examine the laws of motion of 

 falling bodies. At first sight, however, this appears a difficult 

 matter, since different bodies fall with different degrees of 

 velocity. If we take a stone and a piece of thin paper, and 

 let them fall at the same time, the stone will reach the ground 

 before the paper. Most people would say the reason was that 

 the stone was heavier than the paper, but this clearly is not the 

 true reason, for if we take two stones of different weights and let 

 them fall, both will take the same time. The fact is, that they 

 are not falling through an empty space, but through the air, and 

 this offers a resistance to their fall, which increases with the sur- 

 face they present. If we take a piece of gold, and letting it fall 

 from any height, notice how long it takes to reach the ground, 

 and then beat it out into a thin leaf, its weight will not be 

 at all diminished, yet it will fall with much 

 less speed on account of its increase of sur- 

 face. The most conclusive proof that this is 

 the real reason is afforded by what is called 

 the guinea and feather experiment, as shown 

 in Fig. 97. 



A brass cap is made to fit air-tight on to 

 the top of a tall glass cylinder, from which 

 the air can be exhausted by an air-pump. 



Through this cap a small rod passes, by 

 turning which two small flaps can be allowed 

 to fall. Now let a guinea or other piece of 

 money be laid on one and a feather on the 

 other. If the rod be turned both will fall, 

 but the gold will outstrip the feather and 

 reach the ground first, because it meets with 

 less resistance in proportion to its weight. 



Now replace the guinea and the feather 



on the flaps, as at first, but this time carefully exhaust the air 

 from the receiver ; on turning the rod and watching, both will 

 be found to fall in exactly the same time. 



All bodies, then, fall at the same rate, and acquire the same 



Fig. 97. 



