148 INSECTICIDES, FUNGICIDES, AND WEED KILLERS. 



immediately and those which pass on to a branch covered with blue 

 vitriol are likewise poisoned. 



Use against Mammals. — According to Taschenberg, plants are 

 preserved from rabbits, hares, deer, by coating with lime. It is prefer- 

 able to add strong smelling substances, such as petroleum, aloes, lard 

 (rubbing a skin of lard against the trunks of 100 trees suffices). To 

 impart more adherence and thickness to this paste, it is well to add 

 cow dung and thin it down with purin. Seed can be protected against 

 mice by coating them with a thick milk of lime and spreading 

 petroleum thereon. They are then sown immediately after this treat- 

 ment. Such seed are not attacked by rodents. 



Late Frosts. — Lime is successfully used against late frosts. When 

 frost is to be feared, slaked lime in powder is spread on the buds of 

 vines and fruit trees from a bellows so as to cover all their surface. 

 These buds well covered with lime will not be attacked by the frost 

 nor burnt by the sun striking them afterwards. With fruit trees it 

 is necessary to operate before the blossoming of the flowers, or after 

 fructification has taken place. 



44. Calcium Monosulphide. — Preparation. — (1) By heating 

 lime in a current of sulphuretted hydrogen ; (2) by heating a mixture 

 of sulphate of lime and charcoal ; (3) by boiling milk of lime with 

 sulphur ; the polysulphides are so prepared, but by using larger propor- 

 tions of sulphur. The product obtained by boiling milk of lime with 

 excess of sulphur is called calcareous liver of sulphur. The paste 

 bouillies employed to combat plant diseases are of very diverse com- 

 positions, and contain either a basic monosulphide or a monosulphide 

 or polysulphides of calcium. They are generally prepared by boiling 

 a milk of lime with flowers of sulphur, until the latter is completely 

 dissolved. After cooling there are incorporated as occasion requires 

 very diverse substances, such as glycerine, soft soap, copper salts, 

 naphthalene, etc. To prepare and preserve these pastes, enamelled 

 vessels are used. ' The bouillie recommended by Mohr is the one most in 

 use. It is made thus : 22 lb. of quicklime are slaked, then made into 

 a milk of lime and run through a sieve ; on the other hand, 11 lb. of 

 flowers of sulphur are stirred into 2-2 gallons of crude glycerine; the 

 two liquors are mixed and the bulk made up to 22 gallons of liquid 

 which is boiled for one hour over a small fire. A concentrated solution 

 is thus obtained marking 18°-20° B., which is appropriately diluted when 

 required for use, to suit it for particular purposes, with 10-12 pa)-ts of 

 water. It is best to dilute it with a milk of lime of 0'5 per cent 

 strength. Crouzel's anticryptogamic is preparc;d thus : 14 oz. of lime 

 are slaked and the milk of lime therefrom run through a sieve, 35 oz. 

 of sulphur added and the whole completed with water so as to produce 

 150 oz. of bouillie. When a homogeneous mixture is obtained, it is 

 brought to the boil for an hour, care being taken to replace the water 

 evaporated. The solution is filtered or decanted ; it marks 20° B., 0*1 

 oz. of naphthalene is added and 2 oz. of hyprjsulphite of soda, and the 

 whole completed with water to 100 gallons. This preparation is used 

 as it is against the cryptogamic diseases of the vine. 



Properties. — Calcium sulphides are soluble in watex% and in all 



