ACTION OF CARBON BISULPHIDE ON PLANTS. 55 



is almost insoluble in water ; the latter can dissolve at 1000th part of 

 its weight. On the other hand, it is miscible, in all proportions, with 

 absolute alcohol, and with a great number of organic bodies rich in 

 carbon, such as fats, resins, camphors, vaselines. It exercises a very 

 decided deleterious action on the animal economy ; it produces head- 

 ache and nausea, and after a certain time it may debilitate the 

 nervous system. Its intoxications are not generally dangerous, for 

 they cease by the simple removal of the cause. The workmen who 

 handle this product are subject to its effects if precautions are not 

 taken to protect them from the vapours. A dose of 120-150 grammes 

 absorbed by the alimentary canal kills a dog. Carbon disulphide is 

 used in medicine as an antiseptic against typhus, cholera, tuberculosis 

 (Chiandi-Bey), against cancers (Whittaker), intestinal catarrh, and 

 especially infectious diarrhoea (Dujardin Beaumetz), finally as an 

 emmenagogue and ansesthetic. In the form of vapour it is used against 

 helminthiasis and different diseases of the skin (Lewin). 



Action of Carbon Disulphide on Plants. — Carbon disulphide is 

 poisonous to plants. According to Sandsten it stops the movements 

 of the protoplasm as soon as the plant comes in contact with even 

 a very small dose of this agent. It is more injurious to the plant the 

 more its application corresponds with a greater activity of the sap. 

 The same doses used in winter without prejudicing the plants may 

 become deadly in spring or in summer. Carbon disulphide is as in- 

 jurious to the roots as to the part above ground. Plants should never 

 therefore come in contact with pure carbon disulphide, nor into an 

 atmosphere too highly charged with vapours of this insecticide. 

 According to the experiments of Boiteau the roots may die if they are 

 4 inches from the spot where the carbon disulphide was injected 

 into the soil. At the dose of 5 c.c. of carbon disulphide per 4 litres 

 of soil, say at the rate of 5 oz. measures of carbon disulphide per 

 4000 oz. measures (3^ bushels) of soil, the vine would inevitably die ; 

 2 c.c. of the samfi product injected into the same quantity of soil 

 (4 litres) might be injurious to a potted plant. The moisture of the 

 soil tones down to a certain extent the injurious action of carbon 

 disulphide ; its effect is so much the more injurious to the soil the more 

 dry the soil and the higher the temperature. Just as much as con- 

 tact with carbon disulphide and its vapours in strong doses are deadly 

 to plants, so also to a like extent are weak doses indifferent to them 

 when they are brought into contact with the roots either in 1 per cent 

 solution in water, or in the form of vapour. The strong doses applied 

 at the beginning of the phylloxeric invasion always entail the 

 death of the vine, as well as that of its formidable parasite, whilst the 

 cultural doses now used not only do not injure the vine but impart 

 to it exceptional vigour. However, carbon disulphide produces even 

 in a small dose, as Vincey has observed, an injurious action on the 

 plant ; but this action is only a passing one and hardly perceptible. 

 In this way vines treated with small doses of carbon disulphide before 

 the unhairing of the buds are thrown back seven to eight days beyond 

 those not treated. Summer treatment always entails a passing 

 slackening in the growth of the plant. Different plants vary in their 



