By Professor Lindley. 



231 



The foregoing observations were made with two self-registering 

 thermometers, one vertical and one horizontal, laid upon a board, 

 on a bank of snow facing N. W. One of the instruments was made 

 by Knight of Foster Lane, the other by a different person, and both 

 had been compared and tested accurately with a thermometer made 

 by Newman. The register of the horizontal instrument became 

 deranged at the 6~ P. M. observation, the spirit receding from the 

 register, which was lodged against the bend of the tube. The re- 

 maining observations were with the vertical thermometer (Six's), 

 checked by the mercurial side of the horizontal one ; but in the 

 observation at 12| A.M. the mercury had passed the register of the 

 vertical thermometer, so that an allowance of 1° is made on the two 

 last observations for the immersion of the register in the mercury. 



In the interval between the last two observations, the mercury 

 had descended so as to pass the upper end of the register, indi- 

 cating the point it had reached by a globule, which had become 

 detached, and which remained lodged in the bent part of the tube 

 beyond the register, shewing a temperature of at least 5° below 

 zero ; how much lower it was, there was no evidence to prove. 



At Langley Farm, near Beckenham, in Kent, the residence of 

 Lancelot Holland, Esq., it was observed, that on the night of the 

 19-20th of January a thermometer facing the west, six inches above 

 the ground and 20 yards from the house, and from any body which 

 could radiate heat, fell to 13^° below zero. It stood at that point 

 when Mr. Holland examined it a little after seven in the morning. 

 It fell to zero soon after sunset ; at 1 1 P.M. on the 19th it was 3° below 

 that point. In the morning of the 20th, Mr. Holland examined 

 tw o other thermometers attached to the house : the one facing 

 the north was 7°, and that to the west 6° below zero. 



At Redleaf, near Tonbridge, Mr. Wells reports, the cold to 

 have been only 1° on the morning of the 20th, and the ground 

 covered 8 inches deep with snow. 



At Cambridge, according to Professor Hen slow, the thermo- 



