BOOK X. 469 



channel, is two and a half feet wide at the bottom, and two feet and a palm 

 at the top ; and there is likewise no bar at this point ; indeed, not only does 

 the bar not extend to the lower band, but the lower band itself does not 

 extend over this part, in order that the master can draw the litharge out 

 of the crucible. There are besides, in the wall which protects the principal 

 wall against the heat, near where the nozzles of the bellows are situated, 

 two apertures, three palms wide and about a foot high, in the middle 

 of which two rods descend, fastened on the inside with plates. 

 Near these apertures are placed the nozzles of the bellows, and through 

 the apertures extend the pipes in which the nozzles of the bellows are 

 set. These pipes are made of iron plates rolled up ; they are two 

 palms three digits long, and their inside diameter is three and a half 

 digits ; into these two pipes the nozzles of the bellows penetrate a distance of 

 three digits from their valves. The Ud of the dome consists of an iron band 

 at the bottom, two digits wide, and of three curved iron bars, which extend 

 from one point on the band to the point opposite ; they cross each other at 

 the top, where they are fixed by means of iron rivets. On the under side of 

 the bars there are likewise plates fastened by rivets ; each of the plates has 

 small holes the size of a finger, so that the lute will adhere when the interior 

 is lined. The dome has three iron rings engaged in wide holes in the heads of 

 iron claves, which fasten the bars to the middle band at these points. Into 

 these rings are fastened the hooks of the chains with which the dome is 

 raised, when the master is preparing the crucible. 



On the sole and the copper plates and the rock of the furnace, lute mixed 

 with straw is placed to a depth of three digits, and it is pounded with a wooden 

 rammer until it is compressed to a depth of one digit only. The rammer-head 

 is round and three palms high, two palms wide at the bottom, and tapering 

 upward ; its handle is three feet long, and where it is set into the rammer- 

 head it is bound around with an iron band. The top of the stonework in 

 which the dome rests is also covered with lute, likewise mixed with straw, 

 to the thickness of a palm. All this, as soon as it becomes loosened, must 

 be repaired. 



The artificer who undertakes the work of parting the metals, distributes 

 the operation into two shifts of two days. On the one morning he sprinkles 

 a httle ash into the lute, and when he has poured some water over it he brushes 

 it over with a broom. Then he throws in sifted ashes and dampens them 

 with water, so that they could be moulded into balls Uke snow. The ashes 

 are those from which lye has been made by letting water percolate 

 through them, for other ashes which are fatty would have to be burnt 

 again in order to make them less fat. When he has made the ashes 

 smooth by pressing them with his hands, he makes the crucible slope down 

 toward the middle ; then he tamps it, as I have described, with a rammer. 

 He afterward, with two small wooden rammers, one held in each hand, 

 forms the channel through which the litharge flows out. The heads of these 

 small rammers are each a palm wide, two digits thick, and one foot high ; ' 

 the handle of each is somewhat rounded, is a digit and a half less in 



