Sme Adlmns fo W^^ that was pubUJb' d Numb. 5!; 
at Tbolon^t this very year.. 
IN the Defcription of this Channel, McvttA'm JSfumk^^. of 
thefe iraStsy. there was fome mention made of the great Mor 
gazipof Water,: for a continua;! fuppljin cafe of want 
t^hereof.. This Store-hoijfe h more fully defcribed in this Letter; 
where 'tis related^ -"f hat it is in a Valley a little above the 
townof jR<?w4 at St.fmW; and that 'tis to be filled with the^^ 
waters of the Rivokt and thofe of Rain and Snow, that 
are wont to be very plentiful upon the Bkck-m$untain. This 
Valley is TCry narrow at the beginnings large in the middle, and 
flireightened at the foot by the approach of two Rocky Hills, 
bounding it on both fides J which, to make a Lake and to keep 
mxht water , are con^oyn'd by a Caufejt of fuch a height and 
tbicknefs , that it may b^ call'd a third Hill,: This Caftfey is; 
6 1 fathoms broad , and is to be 2 5 fehomshigh, and ^oofatL 
long, togain the Hills on both fides. Thc bajis of this great work 
Is a fblid Body of Mafonry,, laid, aiad every way eneloftd with- 
in the rock.- It hath only a fiiiall Opening below in the form of 
a Vaults which is even with the ground , to fetve for a pafTage to 
the water of this Magazini This pafTage is 9 feet large ^ 1,2 feet 
high, and 94- fathoms lorrg- Upon this Body of Mafonry,, whicji 
by {bmc fathoms exceeds the heigWt of th^^ Vault or Aque» 
duft, there is raifed a thick Wall from^ the tap' of thisDamr 
down in a ftreight line to the foot of it.. This Wall inclbfeth 
wichin its thicknefs another Vault ^ in themanner of a Gallery 
the entry whereof, being at the foot of the Caufey, is of the fame 
heigrh and breadth with the foraier. This Gallery anfwers di- 
^eftly,^ from the top of the Caufey^ to the Orifice of the Aque- 
diift, 5 fathoms above the furface of the ground,, and it runs; 
dawa along tlie fide, and on die left hand ©f the Mouth tiiereoE 
