1S2 TVansactions of the HojiiadfjiraJ Society, 



2T 



5^» 



^ 



obtained : the lower pipe should enter the boiler ■where it has least rend- 

 encv to cool and cherV -^^ ■*- " --^m; t -n. --i-^.^- ^iT-»e from the fire 

 surface. 



7tii, In a dose boL:: .. ^ ^: : the bofler, lise 



to anv heiirhi and descend a^am : nut it vaast neitner nse twice, nor d^ 

 after leavini: the boiler ; where it is necessari- to raise it, there should be an 

 open pipe inserted at each extremirA , of the beaxrhi of the rise : advantage 

 has been taken of this drcumstance to avoid doorways. ( J%. 2S.) 



'' ^tth. A certain cpiHiiiitv df motww wQidd be obtained pt . 

 nr-^r.ta: DiTii berweeu anr pakats t^cspt -Ae bottomF :?^ the vr- 

 ■ t 5ur£acfc, the more naotion wiL J : and, witn oae 



r>e B double current in it- 



• t^TL, Int retardinr effect of fiiction is direri,;. Li tae lenirth, and in- 

 verseiT as the diameter, of the pipes ; it is also increased br ererr bend and 

 angle in th- ^" -" 



*' IS. IL. '.iered the ri minwrrg im ' h. BBOcsarr to the sootiaa o£ 



the fiuid n ;.m. .^r ...-x next enquiry must be tie qnamitT <rf hemt a B«wi^ 

 can convey in e xrrrei: time ; and the qoantitr of surfece tr^ jui n^ to oom- 

 municaxe it to the air ofi the house. It is a &ct net so gataaSfy i Mumu as 

 ii ought to be, that if we communicaxe a certaan 'f"»"''«j' of ht^a*- to a 

 hguid. it will pre out exactly the same quaniirr ag^ao m e o u iiBg to its tar~ 

 mer temperature ; less nor more it i iiiiiiiK afiird. It is egoaDy Ime titxt^ 

 witti the same temperatures, egual and fibe as&cee grre off eooal fjiiMiili 

 ties of iieot to air,&.c. : and. consegueiitlT,^ieqBaiti^ies t^ i-^ e-n t hmMj i l 

 under given circumstances are measurabk goaanUieB, ami dsB ii i dilDi:. eie^ 

 ment is brought within the domaon ofa c Miic e . 



** 14. I iiave shown how to fwliMWIf: tie fmiiiij^ <jf heat required for a 

 forcing-house, in mv bocA on wjmuMg and veodlatb^ (art. 70. and ~1.\ 

 and iiave smce liad to assign the pmpcatiins fir bouses of the largest size, 

 and trie n' ■-• ■!■"-"■ em from the onEnaiy fiinns of an v in this couotr} ; 



