368 



Atmosphere in Houses. 



taining the 5th part of 30, or the 1 50th part of its volume in 

 the state of vapour, of water. At 212° the vapour of water is 

 capable of supporting 30 in. of mercury, consequently at that 

 temperature the whole volume might be water ; at ] 79^° the 

 table would denote about 1 5 in. of elasticity, or a capability of 

 containing one half; at a little above 162°, a 3d part, or 10 in. ; 

 at 80°, lin. of elasticity, or a capability of containing a 30th part 

 of its volume in water, in the state of vapour. The amount of 

 capability for any degree of heat may be thus ascertained, by 

 making the elasticity in the annexed table the numerator of a 

 fraction, of which 30 is the constant denominator. 



= Elasticity of Vapour in Inches of Mercury, from 32° to 212°, according to 



Mr. Dalton. 



Tem- 



Elast. of 



Tem- 



Elast. ofiTem- 



Elast. of Tem- 



Elast. of.Tem- 



Elast. of 



Tera- 



Elast. of 



perat. 



Vapour. 



perat. 



Vapour. perat. 



Vapour. perat. 



Vapour. 'perat. 



Vapour. 



perat. 



Vapour. 



32° 



0-200 



62° 



0-560 92° 



1-44 



122° 



3-50 



152° 



7-81 



182° 



15-86 



33 



0-207 



63 



0-578 



93 



1-48 



123 



3-59 



153 



8-01 



183 



16-23 



34 



0-214 



64 



0-597 



94 



1-53 



124 



3-69 



154 



8-20 



184 



16-61 



35 



0-221 



65 



0-616 



95 



1-58 



125 



3-79 



155 



8-40 



185 



17-00 



36 



0-229 



66 



0-635 



96 



1-63 



126 



3-89 



156 



8-60 



186 



17-40 



37 



0-237 



67 



0-655 



97 



1-68 



127 



4-00 



157 



8-81 



187 



17-80 



38 



0-245 



68 



0-676 



98 



1-74 



128 



4-11 



158 



9-02 



188 



18-20 



39 



0-254 



69 



0-698 



99 



1-80 



129 



4-22 



159 



9-24 



189 



18-60 



40 



0-263 



70 



0-721 



100 



1-86 



130 



4-34 



160 



9-46 



190 



19-00 



41 



0-273 



71 



0-745 



101 



1-92 



131 



4-47 



161 



9-68 



191 



19-42 



42 



0-283 



72 



0-770102 



1-98 



132 



4-60 



162 



9-91 



192 



19-86 



43 



0-294 



73 



0-796103 



2-04 



133 



4-73 



163 



10-15 



193 



20-32 



44 



0-305 



74 



0-823 104 



2-11 



134 



4-86 



164 



10-41 



194 



20-77 



45 



0-316 



75 



0-851 105 



2-18 



135 



5-00 



165 



10-68 



195 



21-22 



46 



0-328 



76 



0-880106 



2-25 



136 



5-14 



166 



10-96 



196 



21-68 



47 



0-339 



77 



0-910107 



2-32 



137 



5-29 



167 



11-25 



197 



22-13 



48 



0351 



78 



0-940 108 



2-39 



138 



5-44 



168 



11-54 



198 



22-69 



49 



0-363 



79 



0-971 



109 



2-46 



139 



5-59 



169 



11-83 



199 



23-16 



50 



0-375 



80 



1-00 



110 



2-53 



140 



5-74 



170 



12-13 



200 



23-64 



51 



0-388 



81 



1-04 



111 



2-60 



141 



5-90 



171 



12-43 



201 



24-12 



52 



0-401 



82 



1-07 



112 



2-68 



142 



6-05 



172 



12-73 



202 



24-61 



53 



0-415 



83 



1-10 



113 



2-76 



143 



6-21 



173 



13-02 



203 



25-10 



54 



0*429 



84 



1-14 



114 



2-84 



144 



6-37 



174 



1,3-32 



204 



25-61 



55 



0-443 



85 



1-17 



115 



.2-92 



145 



6-53 



175 



13-62 



205 



26-13 



56 



0-458 



86 



1-21 



116 



3-00 



146 



6-70 



176 



13-92 



206 



26-66 



57 



0-474 



87 



1-24 



117 



3 08 



147 



6-87 



177 



14-22 



207 



27-20 



58 



0-490 



88 



1-28 



118 



3-16 



148 



7-05 



178 



14-52 



208 



27-74 



59 



0-507 



89 



1-32 



119 



3-25 



149 



7-23 



179 



14-83 



209 



28-29 



60 



0-524 



90 



1-36 



120 



3-33 



150 



7-42 



180 



15-15 



210 



28-84 



61 



0-542 



91 



1-40 



121 



3-42 



151 



7-61 



181 



15-50 



211 

 212 



29-41 

 30-00 



The other requisites to be known as to how far the dew point 

 of the house should be maintained below that point of complete 

 saturation, and the quantity of surface of water required to be 

 exposed to maintain the proper degree of moisture, varies so 

 much with different plants and states of plants and capacities of 

 houses, and has already been so ably explained in the Maga- 

 zine by Mr. Rogers and others, that nothing need be added on 

 that head. — June 3. 1842. 



