ECONOMICAL PLAN OP PROTECTING WALL-TREES. 205 



upwards of 7° below the average. Snow fell on the 15th, there 

 was bright sunshine on the 1 6th ; the evening of that day con- 

 tinued clear, and before morning the thermometer fell iJ5° below 

 freezing ; on the 25th it fell 18°, and on the 28th 24° below the 

 freezing point. The consequence was that plants which were not 

 quite hardy suffered much ; and many were entirely destroyed 

 that had withstood the cold of every winter since 1838. The 

 amount of rain was only one-fifth of the usual quantity, but with 

 two exceptions the air was always found saturated with moisture. 



XV. — An effectual akd unexpenstve mode of Protecting 

 Wall-Trees from Spring-Frosts. 



The following method of protecting his wall-fruit from spring 

 frost has been practised for several years, with great success by 

 John Harrison, Esq., F.H.S., of Snelstone Hall, near Ashbourne 

 in Derbyshire. 



A rod is placed horizontally beneath the coping of the wall. 

 Another horizontal rod is fixed upon posts three feet from the 

 bottom of the wall, and eighteen inches from the ground ; the 

 two horizontal rods are connected at intervals by slight braces or 

 rods as is shown in the annexed woodcut. 



A covering, prepared by sowing woollen netting, on its upper 

 and lower edges, to coarse calico, is then attached to the upper 

 rod by loops and to the lower by pieces of tape ; when the 

 protection is complete. 



Mr. Harrison states that the cost of the worsted net (which is 

 two yards wide), is Is. Scl. per yard running. The calico 

 one yard wide is 2fZ or 2^d. according to quality, and when used 

 is slit down the middle, and one half being sewn to the top, and 

 the other to the bottom of the net, the covering becomes three 

 yards wide. The tape and making up he finds of small cost, 

 while of poles he has abundance of no value. The whole 

 together in London, where every article has to be purchased, 

 ought to be under 2s. a yard running, including making and 

 putting up. 



The walls at Snelstone are brick, eleven feet high, with stone 

 coping which projects about two inches on each side. The trees 

 are unnailed before winter, and fastened loosely to the wall to 



