< 49 <* ) 
But. the Bell defending dill lower, the Pain is renewed,, 
and again eafed after the fame manner. On the contrary, 
when the Engine is drawn up again, the condenfed Air 
finds a much eafier Paflage out of thofe Cavities, and e« 
ven without Pain. This Force on the auditory Paflages- 
might poffibly be fufpecded to be prejudicial to the Organs 
of Hearing, but that Experience teaches otherwife. But 
what is more inconvenient in this Engine, is the Water 
entring into it, fo as to contra# the bulk of Air (accor- 
ding to the aforefaid Rule ) into fo fmall a fpace, as that 
it foon heats and becomes unfit for Refpiration, for 
which reafbn it muft be often drawn up to recruit it.* 
and befides the Diver being almoft covered with the Wa- 
ter thus entring into his Receptacle, will not be long able 
to endure the Cold thereof. 
Being engaged in an Affair that required the Skill of 
continuing under Water, I found it neceflary to obviate 
thefe Difficulties which attend the ufe of the common 
Diving-Bell, by inventing fome means to convey Air 
down to it, whilft below ; whereby not only the Air in^ 
eluded therein, would be refrefh’d and recruited, but al- 
fo the Water wholly driven out, in whatever Depth it 
was. This I effe#ed by a Contrivance fb eafy, that in 
may be wondred it fhould not have been thought of foon- 
er, and capable of furnifhing Air at the bottom of the Sea 
in any quantity defired. The defeription of my Appara- 
tus, take as follows. 
The Bell I made ufe of was of Wood, containing about 
60 Cubick Foot in its Concavity, and was of the form 
of a Truncate-Cone, whofe Diameter at Top was three 
Foot, and at Bottom five. This I coated with Lead fo 
heavy that it would fink empty, and I diftributed the 
weight fo about its bottom, that it would go down 
in a perpendicular Situation and no other. In the Top, 
1 fixed a. ftrong but clear Giafs, as a Window to let in the 
Eight 
