lo Sept., 1910.] Spring Frosts. 603 



results will be obtained by lighting fires as early as possible ; the sooner 

 they are lighted the greater will be the advantage gained. In a general 

 way, they should be started not later than 3 a.m. and kept going until 

 well after sunrise. 



Dense smoke may be produced in many different ways. Heaps of 

 damp straw may be rapidly set on fire with the aid of a little coal tar, and, 

 by stirring occasionally with a fork, kept burning for a long time. At the 

 season when frosts are feared it is good policy to have the headlands un- 

 ploughed — the grass, &c., on them comes in very useful for increasing the 

 volume of smoke, if the straw become too dry. With .small heaps of vine 

 cuttings and straw placed handy for the purpose, and a suitable quantity 

 of green grass, the vigneron can easily maintain enough smoke to save his 

 vines in the case of any ordinary white frost, and these are what one most 

 frequently has to deal with. Against a black frost little can be done, but 

 these, fortunately, are of rare occurrence in the spring. The photograph 

 on page 602 was taken at Chateau Dookie in October, 1900, about an hour 

 after sunrise. The smoke, which was by that time much less dense than 

 pieviously, had been kept going since 3 a.m. in the lower part of the 

 vineyard — the only portion liable to damage. In spite of a pretty severe 

 white frost very little damage was done, thanks to the measures adopted. 

 Tne photograph shows the way in which the smoke drifts, in spite of the 

 air appearmg to be perfectly still. It shows the necessity for preparing 

 all round the vineyard. The line on the lee side need not be lightet' 

 According to Professor Degrully (Montpellier) the fires should be placed 

 right round the vineyard at a distance of fifteen yards apart and lines 

 should run through it at intervals of from 50 to 100 yards, the fires being 

 40 to 50 yards from each other in the line. 



In France, tarry substances are largely used to produce smoke — .some- 

 times coal tar is burnt in iron pots. Specially prepared boxes of resinous 

 substance resembling pitch are put on the market by several manufacturers; 

 some of these are made from the refuse of resin refineries — a by-product 

 from the turpentine industry of the Landes Department. These are very 

 eftcacious, but the price at which they can be landed here is almost pro- 

 hibitive. Lestout's Foyers are of this type. The illustration reproduced 

 from his circular speaks for itself. In France, these cost i franc (about 

 lod. each). They are placed at intervals of 10 yards around the vineyard 

 or orchard and each one burns for four hours. Should wind or clouds 

 remove the danger of frost these " foyers " can be easily extinguished by 

 covering for a moment with an iron box. Being waterproof they can be 

 left exposed to the weather and can be almost instantaneously lighted with 

 a little kerosene and a plug of waste to act as a wick. 



Automatic appliances have been devised which start the fires as soon 

 a"; the temperature falls to a given point. They are somewhat delicate 

 and, on the whole, seem to be more ingenious than reliable. 



Irrigation is a most effectual method of protection against frost. Many 

 of the .submersion vineyards of Southern France are thus ab.solutely saved 

 from frost in low-lying situations where damage from this cause would 

 otherwise be very severe. It is not necessary to completely flood tlie 

 ground ; if this be thoroughly wetted, as in the case of an ordinary watering, 

 damage is prevented even though the temperature in the neighbourhood 

 (where similar protection is not had recourse to) should fall as low as 

 22 deg. F., or even 20 deg. F. 



The application of water in the form of a shower or spray has also 

 been found very effectual. Professor Degrully considers that with large 



