" Jor the Ufe of Artlfts, Manufaaurers, ^c. 123; 



XXI. A Cv'mcnt that hardens under IVatcr. 



Mr. Gad, in the 32d volume of tlie INJenioirs of the Aca- 

 demy of Stockholm, liate>, that if clay and calces (oxide) of 

 iron be plentifidly mixed with oil, they will form a uiafs 

 which will harden even under water. 



XXII. A Glue infoluhle hi IVatcr. 



Leather-dreflers or glovers glue, that of fifli, and that pre- 

 pared with linfced oil, cerufe, and red lead, which cements 

 pretty llrongly glafs, ftone, and wood, iiill leave room to 

 wifli for one of a Wronger quality. 



An excellent glue may be procured from cheefe. Take 

 fkim-mijk cheefe, free it from the rind, cut it in flices, and 

 boil it in warm water, ftirring it with a fpoon until it be 

 reduced to a (trong glue which does not incorp'-rate with 

 water. Then throw away the warm water, poiu- cold water 

 over the glue, and knead it afterwards in warm water, fub- 

 jecling it to the fame procefs feveral times. Put the warm 

 glue on a grinding (lone, and knead it with quicklime until 

 you have a good glue. When you wifli to ufe this glue yoa 

 niufl: warm it : ifit be employed cold it is not fo ftrong, but 

 it may aifo he ufed in that manner. This glue is inloluble 

 in water as foon as it is dry, and it: becomes fo in forty-eight 

 hours after it has been applied. It may be ufcd for gluemg 

 wood, and for cementing marble and' broken ftone, and 

 earthen ware. The joining can fcarcelv be dilcovered. 



Baits alfo for catching fifb may be made of it. Fifli ar»i 

 very fond of it, and it refifts water. Boerhaave obfervcd that 

 no menftruum diiiblved cheefe, not even aqua-regia. — Tranf- 

 anions of the Academy of Sciences at Stockholm. 



XXIII. A Cement that luill Jfand agahijl hoU'mg JVdter^ 

 and even bear a cnnfiderahie Pre[fure of Steam. 



In joining the flanches of iron cylinders and other parts of 

 hydraulic and fteam-engines, great inconvenience is often 

 experienced from the want of a durable cen)ent. 



Boiled linfeed oil, litharge, red and white lead, mixed to- 

 gether to a proper confidence, and applied on each fide of 

 a piece of flannel, previouily (liaped to fit the joint, and then 

 interpoftd between the pieces before they are brought home 

 (as the workmen term itj to ihcir place by the fcrew'sor other 

 faftenings employed, make a clofe and durable joint. 



The quantities of the ingredients may be varied without 

 inconvenience, only taking; care not to make the mafs too 

 ^hin with the oil. It is difficult in uiany cafes iullantly to 



ntakc 



