* [ M 8 ] 
the Figure annex’d denotes j for in cafe one would 
not beftow Iron Hoops on the Bellows , they might 
be made fquare, in a Triangle, or any other Shape, 
provided they be as wide again at Bottom as at top i 
and if they be made of Wood, it will be neceflary 
to provide an Edge round the Tops, for containing 
Stones or Leaden Weights, as much as will be found 
neceflary to make them fink readily, when they are 
lower’d down into the Water. 
Laftly, If we will confider the Charge of thofe 
Bellows made ufe of at Iron Furnaces, as to the 
Bellows themfelves, the Water-Wheel and its Axle- 
tree, &c. and compare the fame with the Coft of 
thefe, we (hall eafily find a vaft Difference, not to 
mention the vaft Charges of keeping the common 
Bellows in Repair. But before I conclude, I think 
myfelf obliged to mention, that the Blaft of thefe 
Bellows is govern’d and moderated in the fame man- 
ner as the common ones, viz. by letting more or lefs 
Water into the flopeing Gutters, and by taking out 
and letting in Plugs for that purpofe placed in Holes 
near the Top of the Water-Bellows. 
Stockholm , Martin Triewald, F. R, S. 
Majiz, 1736' - 
II. Vtrt 
