< 449^ ) 
would, according to the nieafure fixed above , make 3 1 miiiion^ 
and 245 1 44 fathoms infiirface. In this Confervatory imagine^ 
that during a whole year there has fallen Rain to the height of 
1 9 inches 2 lines, as was faid before* This hcighc of 1 9 inches 
and 2j lines gives 280 millions §99942 muidsoi water, or there- 
about, according to themeafure fuppofed» 
All this Water thus collefied in the quantity juft now exprefTed^ 
is that ftock which is to ferve to make this River. run for a 
whole year, from its fource to the place before-named, and which 
muft alio ferve to fupply other occafions andloffes, fuch as are 
the feeding of Trees, Herbs, Vapors, and extraordinary Iwellings 
of the River whilft it rains, and deviations of the water running 
another way. 
Concerning themeafure or cftimate of the water of this rifing 
River, it would be difficult to find it juft and precife , and to 
determine what quantity it furniflies. Yet fofaras I was able to 
judge, it can have no more than a looo or r 200 inches of water 
alwaies running, compenfatlng the lefler quantity ic hath at its 
fource with the greater it hath towards JimyUDuci The which 
I fo judge by the comparifon I make of thefe Waters with ihofe 
oftheRiverof the Gobelins^ in the condition wherein it is to- 
wards T^rpi/i^y, where it hath fifty inches of water, according to 
the meafuretaken of it. So that I efteem, it will be enough to 
allow twenty four or twenty five times as much to our River* 
For the Channel of it' is to be four or five fathoms large, and for 
depth 'tis btitlhallow ^ it carries no Boats,and fcrves only to Boat 
down fome loofe Billets, 
Thefe particulars being thus fu ppofed, I fay, that according 
to the meafijres we have agreed upon , 1 200 inches of water do 
furnifii in twenty four hours , after the race of 85 ^///Wi of water 
to an inch, they furnifhj I fay, 99600 muids of water ; where- 
fore, for a whole yea which is near 366 times as much, they will 
furnifii 36 millions 453600 
This River then fends away within its banks, in a year, no 
more than about 34^: millions of muids water. But taking this 
quantity out of the 280 millions that are in the Confervatory 
above defcribed , there will remain yet above 188 millions of 
muids y which amounts to almoft five times as much, and which 
ferves to furnifli for the loflTeSj diminutions , and other wafles, 
above taken notice of. So that there needs bur the fixih part of 
~ "^; the 
