/ 
1 ^h[aturall HiHory: 
being further off(as vpon a large Riuer) they make an Iterant Eccho: For 
there is no difference betweene tbeConcurrent Eccho,and the I ter ant Jam 
the Quicknefle,or Slowneffeofthe Returne.But there is no doubt,but 
watered oth help the Delation of Eccho • as well as it helpeth the Delation 
of Originall Sounds. 
Itiscertaine ( as hath beene formerly touched, that if you fpeake 
thorow a Trunke, flopped ajjrhe further end, you fhall finde a Blaft re- 
turne vpon your Mouth, bnrno Sound at all. The Caufe is, for that the 
Clofensjfe , which preferueth the Original!,is not able to preferue the Re- 
fleUed Sound ;Befides that Eccho s are feldome created but by loud 
Sounds . And therefore there is leffe hope of Artijiciall Ecchocs in Aire, 
pent in anarrowConcaue.Neuertheleffe it hath bin tried,that One lea¬ 
ning ouer a well, of 2 5. Fathomc deep,and fpeaking,though but foftly, 
( yet not f‘o foft as a whifper) the water returned a good Audible Eccho. 
It would be tried whether Speaking in Caues, where there is no Iflue, 
faue where you fpeake, will not yeeld Eccho s, as Wells doe. 
The -E^/wcommeth as the Originallsound doth, in a Round Orbe of 
Aire : It were good to try the Creating of the£c^, where the Body 
Repercufling maketh an Angle: Asagainft the Returne of a Wall, 
I &c. Alfo we fee that in Mirrours, there is the like Angle of Incidence, 
from the Obie<5t to the Glafle, and from the Glafle to the Eye. And if 
you ftrikea£d//fIde-long, not full vpon the Surface, the Rebound will 
be as much the contrary way • Whether there be any fuch Refilience in 
Eccho’s,(tkat is, whether a Man fhall heare better, if he fland afide the 
Body Repercuffing,than if he fland where he fpeaketh,or any where in 
a right Line betweene;) may be tried. Triall likewife would be made, 
by (landing neerer the Place of Repercufling, than hee that fpeaketh •, 
And againe by (landing further off, than he that fpeaketh - } And fo 
Knowledge would be taken,whether Eccho’s, as well as Orignall Sounds, 
I be not ftrongeft neere hand. 
There be many Places, where you fhall heare a Number of Eecho’s 
one after another: And it is when there is variety of Hills or woods, 
fome neerer, fome further off;So that the Returne from the further,be- 
gng laft created, will be likewile laft heard. 
I " 1 A s the Voice goeth round, as well towards the Backe, as towards the 
FroSt ofhim that fpeaketh ; Solikewife, doth the Eccho $ For you haue 
many Back -Eccho’s, to the Place where you (land. 
To make an Eccho, that will report, three, or foure, or flue Words,? 
diftin&Iy, it is requifite, that the Body Repercuffng, be a good diftance 
off; For if it be neere, and yet not fo neere, as to make a Concurrent Ec¬ 
cho, itchoppeth with you vpon the fudden.lt is requifite likewife, that 
the Aire be not much pent. For Aire, at a great diftance, pent, worketh 
the fame effect with Aire, at large, in a fmall diftance. And therefore in 
the Triall of Speaking in the Well? though the Well was deepe, the Voice 
came backe, fuddenly 5 And would beare the Report but of two 
Words. 
For 
