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. In Foix in France.

In the county of Foix, the blowing machines, as de-scribed by Reaumur in the art des forges above quoted,are considerably different from the foregoing. The pipeis rectangular, and the part above the choak divides intothree funnel-shaped partitions. On the top is a reservoiror cistern of water ; and two of the partitions, close on allfides, pass up above the surface of the water, for carryingdown air, and thus supplying the place of the lateral airholes : the water enters into the third partition, whichis only the space between the two foregoing, and whichhas but two fides, formed by the two opposite sides of theothers.

The author makes the principal difference of these ma-chines from those of Dauphiny to consist in this dispo-sition of the upper part: but the plate, annexed to hisdescription, shews another, which is, perhaps, more ma-terial to the effect of the instrument. The whole heightof the pipe, including that of the water in the reservoiron the top, is, according to the scale, twenty or twenty-one feet, and the choak or narrow throat is almost downat the middle of this height; so that the water issuesthrough the choak with a velocity which it acquires froma pressure of about ten feet, which is greater than in themachine of Dauphiny in the proportion of about elevento six : the quantity of water seems also to be much lessIn proportion to the width of the pipe, the great pres-sure probably occasioning it to spread, so as to fill a largerbore than it could do when falling with less velocity.

Two pipes, divided in the fame manner at the top, arefed by one reservoir : the lower ends of the pipes enterinto one large oblong box, from which the air and waterpass out as in the foregoing machines.

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