230 EEV. C. AY. HARVEY — FROST OF JANUARY, 1881, 



The severe frost may be said to have commenced generally on 

 Jan. 13th, and to have lasted until the 26th, on which day the thaw 

 set in. The minima on the 27th were in some cases very low, but 

 my own experience leads to the conclusion that these minima 

 represent the actual temperature of the previous morning when the 

 instruments were last set. 



The total range of temperature during the fortnight was fi'om 

 39° at Oaklands, Watford, and 38° at Bayfordbury, on the 23rd, to 

 4° at Nash Mills and Bayfordbury on the 21st; a thermometer at 

 the lodge of the latter place, fixed a few inches from the ground, 

 registering — 3°. The total range of temperature was consequently 

 35°. The lowest day temperature was 20°-5 at Stevenage on the 

 16th, while the highest night temperature was 26° at Bayfordbury 

 on the 13th; thus the day range was 18°-5, the night range being 

 22°. The highest mean temperature was that for the 23rd, namely 

 27°-4, the lowest being 18°-5 on the 21st. On the 23rd the day 

 temperature was at its highest, the mean being 34°* 2 ; while on 

 the 21st the night temperature reached its lowest point, the mean 

 being only 8°* 5. 



From this it appears that on the whole the IS'orthern district 

 experienced the greatest cold, the mean temperature for each 

 district being, S. 22°-2 ; C. 22°-9 ; N. 21°-6. The night temperature 

 was slightly lower in S. than in N., the C. district showing 

 the highest mean ; the values being, S. 15°-2; C. 16°- 1 ; N. 15°-5 ; 

 while the day temperature was considerably lower in the north, 

 the values being, S. 29°- 1 ; C. 29°-7 ; N. 27°-8.*- 



Having said thus much of the frost generally, I will now 

 proceed to speak more particularly of each separate day. 



Thursday, 13th. — Mean temp. 26°-l. Night temp, lowest in S., 

 day temp, in IST. Minima ranged from 26° at Bayfordbury to 15° at 

 Southgate ; the mean being 20°*5. Maxima ranged from 33° at 

 Southgate, Berkhampstead, and Bayfordbury, to 29°- 9 at Throcking ; 

 the mean being, 31°-7. 



Friday, 14th. — Mean temp. 20°-4. Night temp, lowest in C. 

 and N districts, day temp, in S. Minima ranged from 20° at 

 Gorhambury ancl 18° at Moor Park, Eickmans worth, to 10''"5 at 

 Oaklands, Watford; the mean being 15°- 1. vT/^-XM^rtt ranged from 

 32''-4 at Royston to 22''-l at Throcking ; the mean being 25"-7. 



Saturday', 15th. — Mean temp. 19''-3, Night temp, lowest in S., 

 in 5 instances minima were registered below 10" ; day temp, lowest 

 in N. Minima ranged from 18° at Gorhambury to 7° at Oaklands, 

 Watford; the mean being ll''-5. Maxima ranged from 31° at 

 Bayfordbury to 23°-2 at Royston, the mean being 27°"1. 



Sunday, 16th. — Mean temp. 20°- 6. Night temp, lowest in S., 

 minima in three instances registered below 10° ; day temp, lowest 

 in N. Minima ranged from 18° at Knebworth to 8°-7 at Wansford 

 House, Watford; the mean being 14"-2. Maxima ranged from 31° 

 at Bayfordbury, to 20°-5 at Stevenage ; the mean being 27°. 



* Of all the stations Nash Mills shows the lowest means both of max. and min. 

 temperature. 



