380 



Letter from Prof. Forbes to the 



Table continued. 



Date. 



1827. 

 Jan. 24. 

 25. 



26. 



27. 



28. 

 30. 

 31. 



Thermo- 

 meter 



620 

 570 

 61-0 

 600 

 550 

 60-0 

 610 

 530 

 630 



Time. 



2 p.m. 

 6 a.m. 

 2 p.m. 

 2 p.m. 

 6 a.m. 

 2 p.m. 

 2 p.m. 

 6 a.m. 

 2 p.m. 



Leslie's 

 Hygrom. 



330 

 220 



27-5 

 220 

 22-0 



49-5 



Time. 



Remarks. 



1 p.m. Cloudy and Showers. 



Id. 

 Id. 

 Id. 

 Id. 



Fair. 



30 days 62°-87 max. |. 590.5 ^g^,^ Hygrometer mean 40°-38. Var. 55° 



?8'd^?!5T38min.-}^l°^^-'^- Hygrometer 57°-07. Var. 55°. 



Weather generally fine. The beginning of the month remarkably 

 clear; all the snowy mountains of the horizon of Quito being visible. 



March I 62° '42 max. ) rno o>r 1 u i. oco *Tn \r aa^ 



31days.)56-63min. ) ^^^^7.ned. Hygrometer 35-79. Var. 44" 



Weather generally rainy and 'cloudy. 



24^days. | sf 71 mi'n'.' } '^^^^e med. Hygrometer 33°-65. Var. 55^. 

 Weather as in the preceding month. 



Mean of four months | gg^.gg Hygrometer 41<'-69. 

 from January to April j •'° 



July to December 1826,1 500.97 

 14 months ] 



18 months ; mean temperature of Quito 59''"96. 

 July 1825 to April 1827. Hygrometer 4 months 41°-69. 



[To be continued.] 



LVII. Letter to the Editor of the Scientific Memoirs respecting 

 a Paper on the Polarization of Heat, in the Sixth Number 

 of that Journal. By James D. Forbes, Esq., F.R.S.L. SfE. 

 Professor- of Natural Philosophy in the University of Edin- 

 burgh. 



To Richard Taylor, Esq. 



My DEAR Sir, Edinburgh, Oct. 15, 1839. 



THE translation of Mr. Melloni's paper on the polariza- 

 tion of heat, part ii. which appeared lately in the sixth 

 Number of the Scientific Memoirs, contains critical remarks 

 on my experiments in almost every page. I have long hesi- 



