8 4 



HA RD WICKE'S SCIENCE- G SSIP. 



common food of all, the starch, sugar, gum, etc., 

 that are good and wholesome, and others the alkaloids 

 and bitter, acrid principles, the "poisonous wine" of 

 the poet ? Alkaloids, of course, partake somewhat 

 of the nature of the alkalis soda and potash that are 

 found in all vegetables, and mostly occur in com- 

 bination with the acids of the plant ; they are said to 

 be the most remarkable substances discovered by 

 modern chemistry, and are the active principles of 

 those plants in which they are found. But although 

 they are, so to speak, the very essence of the plant, 

 they are not necessary to its life and well-being, but 

 are waste products, substances that the plant wants 

 to get rid of, for they take no part in the formation 

 of its tissues. They are, therefore, usually removed 

 from, the younger and most active parts, and are 

 stored up as secretions in bark, fruit, seeds, etc., in 

 the case of Aconitum chiefly in the root. Vegetable 

 alkaloids are composed essentially of carbon, hydrogen , 

 and nitrogen, the greater number also contain oxygen, 

 but nitrogen is invariably present. These poisonous 

 principles are most energetic in their action on the 



Fig. 44. — i, fruit of Conium maculatum (enlarged}. 2, longi- 

 tudinal section of one carpel and seed ; 3, transverse section 

 of same, showing the deeply-furrowed albumen. 



human system, and many are used as medicines 

 which in large doses would be poisonous. They are 

 named after the plants in which they are found : 

 Belladonine, Atropine, Morphine, Nicotine, Theine, 

 etc., and the very powerful alkaloid that is obtained 

 from Aconitum napdlus is called aconitia or aconitine. 

 Aconite is, it scarcely need be said, one of the most 

 valuable of medicines, and has been called the 

 " homoeopathic lancet" on account of its wonderful 

 power of reducing fever, indeed it is to the introduc- 

 tion of this drug into the modern practice of medicine, 

 that we are largely indebted for the more rational 

 treatment of fevers that now prevails. It is to be 

 noted that alkaloids in their most concentrated form 

 are crystalline and colourless — can the Raphides that 

 abound in some plants of the Lily tribe be of this 

 nature, for the Scillas and Colchicums have an 

 undoubtedly poisonous character ? Aconitine belongs 

 to the class of narcotic irritant poisons. 



Next in order, and not less pernicious in their 

 effects upon man and animals are the three or four 

 members of the Umbellate family that possess 



noxious qualities : these are Conium maculatum, hem- 

 lock ; Cicuta virosa, water-hemlock or cowbane, and 

 CEnanthe crocata, hemlock dropwort, or dead- 

 tongue. (Ethusa cynapium is also poisonous, and 

 from having been mistaken and eaten for a most 

 useful and wholesome member of the same family 

 has been named "fool's-parsley." Conium macu- 

 latum is indigenous, and has long been used in 

 medicine ; its nauseous smell when bruised ought to 

 be enough to warn any one from it. Unlike Aconi- 

 tum napdlus, it is in the fruit that the poisonous, 

 properties of hemlock are concentrated, and con- 

 sidering that it is an annual plant, it is only to be 

 expected that they would be stored up in the albumen 

 of the seed. The fruit, though resembling that of 



Fig. 45. — Section of flower of Jlonkshoad. 



Fig. 46. — Napiform roots. 



cowbane and celery-apium, differs from them in its 

 deeply-furrowed albumen. The active principle is- 

 Conia, an oily alkali with a peculiar mouse-like 

 odour. Hemlock being the state poison of Athens, 

 was that used to compass the death of " that best, 

 wisest, and most just of men," Socrates. The 

 action of this narcotic irritant poison is to paralyze 

 the muscles of respiration so that death is compara- 

 tively painless. Plato relates in the Phaedo how the 

 servant who brought the poisoned cup to Socrates 

 told him to walk about until his legs felt heavy, and 

 then lie down, — " the drink," said he, "will do the 

 rest ;" and how gradually he grew cold and stiff from 

 the feet upwards, and said to those around him that 

 when the cold reached his heart, he should depart ; 

 then, uncovering his face, he gave that famous last 



