330

Perier’s Engines.

[Book III

unusual number of illustrations required in this cbapter, it is omitted. Ashort description will suflice. After describing an atmospheric pump be-longing to the arsenal of Paris , and another attached to a hotel in the fau-bourg St. Antoine, which had two spouts and two valves in the suctionpipe, the author observes, J’ay vu a Paris des pompes dont on se sert pourtacher d’ eteindre le feu quand il arrive des incendies; and he then entersinto a minute description of one of these Parisian engines. In its generalappearance it resembled the Dutch one No. 148, consisting of two work-ing cylinders with an air vessel between them, the piston rods moved bya double lever, through the ends of which staves four f'eet in length wereinserted. The pump cylinders were sixteen inches long and four in dia-meter, but instead of being placed in a square wooden box or cistern,they were secured in an open copper pan, of an oval shape, and the samedepth as the cylinders, and fastened by bolts to a base of wood or pieceof plank, to the four corners of which short ropes were fastened. At oneend of the pan, the leather hose which conveyed the water to the fire wasconnected by a screw to a copper pipe that communicated with the lowerpart of the air chamber. The leather tubes, Polmiere observes, werelubricated with a composition of tallow and wax to render them pliable;and, to prevent mice and other vermin from destroying them, soaked inan infusion of colycinth or bitter apple. In furnishing the pumps withwater, Perier adopted the first device of the Van der Heides, and hencewe infer that he was ignorant of the better mode of making them supplythemselves through suction pipes. As they could only draw water out ofthe vessel in which they were placed, and it being too small and inconve-nient for numbers of people to pour the contents of their buckets into itwhen the engine was in use, a canvas or sail cloth bag, coated withpitch or tar, was connected by a flexible pipe of the same material, to thelower part of the pan. This bag was of a conical form, the wide end be-ing uppermost, and supported with the mouth open on a folding frame,something like a high camp stool. Into this bag the water for the supplyof the pumps was poured. It might of course be placed at any conveni-ent distance from the engine, by means of additional lengths of pipes thatwere always kept ready and which were connected together by screws.These engines, Poliniere says, forced the water through the orifice of thejet pipe to a surprising distance. He observes also that smaller ones werein use; which consisted of a single cylinder and air chamber, and wereworked by a single lever.

The following extract relating to Perier’s engine is from the Diction-naire CEconomique, 3d. edit. Paris , 1732, from which it appears that atthat date they were small affairs, and differed but little from our gardenengines ; in other words, they were then nothing more pompes porta-tive, the name by which they were designated at the first. “ La pompeque le Sieur du Perier a inventee ou perfectionnee est trbs commode dansles incendies. Deux hommes la peuvent aisement transporter avec toutson attirail, et la placer dans tel lieu que l’on voudra. II n’est pas neces-saire qu’elle soit dans l’endroit ou se trouve l’eau, il y a un canal de coutilcire en dedans,' qui sert a conduire l’eau jusqu’a’la pompe. Ce canalpeut 6tre augmente en y adaptant d’autres canaux faits de la mbme facon.La pompe etant placee dans le lieu le plus commode, ou peut encore por-ter l’eau dans le plus fort de l’incendie par le moien d’un canal, qui estfait de cuir, et qu’on augmente, autant qu’on veut, en y ajoutant d’autrescanaux par le moien de quelques vis. La matiere dont est compose, cecanal donne la facilite de passer d’un appartement dans l’autre pour ap-pliquer l’eau dans l’endroit le plus necessaire. Les circonvolutions du