Qcntury 1 1 I 



th an the koife is heard. And in Hewing Wood, if one be fomediftance 

 off, he (hall lee the Arme lifted up for afecond Stroke, before he hear the 

 Noife of the firft. And the greater the Diftance,the greater is the Preventi- 

 on ; As we fee in Thunder, which is tarre off ; where the Lightning prece- 

 deth the Crack a good fpace. 



I Colours, .when they reprefent themfelves to the Eie, fade not,nor melt not 2 i I 

 by Degrees, but appear ftill in the fame ftrength h But Sounds melt, and 

 vaniih,by little and little. The Caufe is,for that Colours participate nothing 

 with the Motim of the Air $ but Sounds do. And it is a plain Argument, 

 that Sound participateth of fome Locall Motion, of the Air-, (as a Caufe 

 Sine qua non,)m that, it perimeth fo fuddenly •, For in every Section, or 

 Impulfion of the Air, the Atr doth fuddenly reftore and reunite it felf 

 which theWater alfo doth, but nothing fo fwiftly. • 



In the Trials of the Paffage, or Not Paffage of Sounds, you Experiments 



muft take heed, you miftake not the Pafjing by the fides of a ["uchingVhe 

 Body, for the Faffing tborow a Body : and therefore you muft 



make the Intercepting Body very clofe $ For Sound will pafs of Smnds - 

 thorow a frnall Chinck. 



Where S ound y&tth thorow a Hard, or Clofe Body (as fhorow Water ^ 212 

 thorow a Wall h thorow M etall, as in Hawkes Bels ftopped, &c.) the Hard 

 or Clofe Body, muft be but thinne and fmall For elfe it deadeth and extin- 

 guiiheth the Sound utterly. And therefore,in the Experiment of Speaking in 

 Air under Water, the voice muft not be very deep within the Water: : For 

 then the S ound pierceth not. So if you fpeak on the further fide of a Cloje 

 Wall, if the Wall be very thick, you ihall not be heard : And if there were an 

 Hogihead empty, whereof the Sides were fome two Foot thick, and the 

 Bung-hole Hopped : I conceive the Refotmding Sound, by the Communica- 

 tion of the Outward Atr, with the Air within, would be little or none : but 

 only you lhall hear the Noife of the Outward Knock, as if the Veflell were 

 full. . 



It is certain, that in the Pag age of Sounds thorow Hard Bodies, the Spi- 21? 

 ritor Pneumaticall Part of the Hard body it felf, doth cooperate h But 

 much better, when the Sides of that Hard Body are ftrttck, than when the 

 Percuffion is only within, without Touch of the Sides. Take therefore a 

 Hawkes Bell, the holes flopped up, and hang it by a threadjwithin a Bottle- 

 Glafs-, And ftop the Mouth of the Glafs, very clofe with Wax, and then 

 (hake the Glafs, and fee whether the Bell give any Sound at all, or how 

 weak? But note, that you muft in ftead of the Thread, take a Wire.; or 

 elfe let the Glafs have a great Belly «, left when you make the Bell, it dam 

 upon the Sides of the .Glafs. 



It is plain that a very Long, and Down-right Arch, for the Sound to pafs, 214 

 will extinguilh the Sound quiet-, So that that S ound, which would be heard 

 over a Wall, will not be heard over a Church-, Nor that Sound, which will 

 be beard, if you ftand fome diftanee from the wall, will be heard if you 

 ftand clofe under the Wall. 



Soft and For aminous Bodies, in the firft Creation of the Sound, will dead it 2 1 5 

 For the ftriking againft Cloth, or Furre, will make little Sovind \ As hath 

 been faid : But in the Parage of the Sound, they will admit it better than 

 Harder Bodies As we fee,°that Curtaines, and Hangings, will not ftcy the 

 Sound much; But Glafs- windowes, if they be Very Clofe, will check a 



F 2 Sound* . . .. 



