1872.] Mr. W. Whitehouse on a New Hygrometer. 183 



mean time the writer has been advised to offer, at the earliest time, a brief 

 description of it to the notice of the Royal Society. 



Table. — Giving comparison of Readings of Wet- and Acid-bulb 

 Hygrometers. 



1871. 



Mason's 

 Hygrometer. 



Mr. White- 

 house's. 



Deductions from 

 Wet-bulb 

 Hygrometer. 

























elative Humi- 

 dity. Satura- 

 tion = 100. 



Kemarks. 



Day. 



Hour. 



Dry 

 Bulb. 



Wet 

 Bulb. 



rS H 



Acid 

 Bulb. 



ifference, 

 A-D. 



;nsion of 

 Vapour. 



'"eight of 

 pour in 1 

 foot of A 















A 





P 



EH 











Acid flow 



ing 



from 



bul 



bid 



rop 1 



n 33 



secon 



ds. 







h. 



m. 



















- 



in. 



giO. 







Nov. 6 .. 



IO 



7 A.M. 



40*0 



36*0 



4'° 



6o - 2 





172 



2"0 







IO 



30 „ 



4°*5 



36-3 



4-2 



61-5 



21 '0 





2*0 



6q 



7 







ii 



25 » 



41-0 



367 



4"3 



6i*3 



&KJ 5 



•T7C 



2"0 



68 





"At noon the wet 





ii 



33 »» 



4i - o 



37-0 



4-0 



62*0 



21 'O 



•l80 



2 - I 



7° 





bulb was washed 





i 



4 P.M. 



43"° 



38-0 



5"° 



64*0 



2I"0 



•l8l 



2"I 



65 



1 



and resupplied 



» • • 



I 



5° » 



44'° 



3 8 5 



5'5 



05*2 



21*2 



'l80 



21 



62 





with water. 





2 



5 » 



44'° 



39° 



5'° 



^5*3 



21'3 



•l88 



2'2 



6 5 



i 



3ky has gradually be- 





2 



20 „ 



43'7 



38*8 



4*9 



*>5'9 



22*2 



•l88 



2'2 



66 



come overcast since 





2 



3° » 





1 Q'O 



CO 





217 



•l88 



2"2 



65 



the morning. 





3 



30 >» 



44'° 



39"3 



47 



66-3 



22 - 3 



•193 



2'3 



67 





» 



2 





TT 



T.Q'6 



A. 'A. 



T \ 



67*0 



23*0 



190 



2'3 



Do 





r Note the change in 















IN C V . I 



9 



45 A.M. 



45'° 



43'° 



2'0 



75'° 



3°'° 



•253 



2- 9 



85 



1 



night ! Dark and 























foggy day. 





IO 



IO „ 



45'5 



44-0 





77-8 



3 2 '3 



"270 



3* 1 



6 9 





:o 





IO 



20 „ 



46-0 



44' 2 



i-8 



76*0 



30*0 





3' 1 



/ 







IO 



3° » 



46^0 



44-2 



r8 



76*2 



30-2 



•269 



3-i 



87 







II 



5 » 



46-8 



45'° 



i-8 



75-2 



28*4. 



"277 



VI 



j 



87 



(0 





1 1 



35 » 



477 



45-6 



2*1 



78-0 



30-3 



•276 



3' 2 



87 









15 P.M. 



50*0 



47-0 



3'° 



82-0 



32*0 



•286 



3'3 



80 



Vapour has increased, 





3 



*5 » 



5o - o 



47 'o 



3'° 



82-4 



32'4 



•286 



3'3 



80 



but humidity has 



>» 



3 



5° » 



5°*° 



47-0 



3'° 



82-9 



3 2 '9 



•286 



3-3 



80 



decreased. 





4 



„ 



50*0 



47 -o 



3-0 



83-0 



33'° 



•286 



3'3 



80 







5 







49"5 



46-5 



3-0 



83-5 



34'° 



•28l 



3'2 



80 







6 



„ 



49*5 



46-5 



3"° 



82-5 



33-0 



•28l 



3' 2 



80 





» • • 



8 



„ 



5 ro 



47 'o 



4-0 



81-5 



3°'5 



•276 



3'i 



74 





Nov. 8 



9 



» 



49'5 



46*0 



3'5 



795 



3°'° 



•270 



3'° 



76 





" Sky overcast ; slight 

 misty drizzle. 





IO 



40 A.M. 



47-5 



45-5 



2 - 



8i-8 



34-3 



•280 



3'3 



86 



1 

















387 







84 





" Yapour increased ; 





IO 



5° » 



5°"3 



48-0 



2- 3 



89-0 



•305 



3'5 



< 



humidity deer. 





1 1 



15 „ 



50*0 



47-6 



2-4 



88-o 



38-0 



•3OO 



3 '4 



83 





» • • 



1 1 



2 5 » 



50*0 



47 "o 



3-0 



85-3 



35'3 



•286 



3'3 



80 





' Sky clearing since 



11.25 A.M. 



Humidity greatly re- 







NOON 



5°'3 



47'° 



3'3 



82-0 



3/7 



•283 



3'3 



78 









50 P.M. 



51-0 



45*5 



5*5 



8ro 



30-0 



•246 



2-8 



63 





duced; vapour not 















so much. 

 Yapour decreased in 





2 



30 ». 



497 



43-0 



67 



75-2 



25-5 



•2IO 



2-4 



59 





greater proportion 





3 



O „ 



49-0 



43' 2 



5-8 





27-0 



•221 



2'5 



63 





than humidity. 



>> 



3 



5° » 



487 



43'° 



57 



747 



260 



•219 



2'5 



66 





VOL. XX. P 



