294 



EECKEATIYE SCIENCE. 



TJiey are then taken out of the water, and 

 spread out to dry and bleach in the sun. The 



Fig. a. 



whole, except the woody fibre, is now become 

 very brittle ; it is then beaten and chopped 

 between stout pieces of wood arranged for 

 the purpose, and the fibre separated from the 

 rest of the vegetable matter. It is then 

 combed, and tied up into convenient-sized 

 bundles for home use or sale. 



The roots of the hemp are very liable to 

 be attacked by one of the species of that 

 curious tribe of parasitical plants the Oro- 

 hanche, and, from its stem being branched, it 

 is called the O. ramosa (Fig. 3). It grows 

 from six to twelve inches high, is of a pale- 

 yellowish brown colour, and bears a few 

 scattered brown membranous scales in the 

 place of leaves ; its flowers are numerous, of 

 a pale purplish colour. An ordinary-sized 

 plant bears about sixty-six capsules, and in 

 each there are about 1100 small, but very 

 beautiful-looking seeds; so that one plant 

 alone furnishes no less a number than 72,600 

 seeds ! each of which is capable of producing 

 a plant, and as the seeds of the Orobanche 

 are known to remain a considerable time in 

 the ground without losing their vitality, the 

 chances of their idtimate development on 

 the roots of the hemp are increased. 



I have observed, in a field where the hemp 

 has grown, the roots very much infested with 

 this plant, but 

 still the plants 

 of the hemp on 

 which it grew 

 were apparently 

 uninjured by 

 it. The field 

 was sown with 

 wheat, turnips, 

 and other crops, 

 on, I believe, 

 the five suc- 

 ceeding years ; 

 but not a plant 

 of the Oro- 

 banche was to 

 be found, but 

 hemp was again 

 sown, and then 

 there sprang up 

 an abundance of 

 this pretty parar 

 sitical plant- 

 In the sap of 

 the hemp there 

 exists a peculiar 

 resinous sub- 

 stance, which 

 possesses nar- 

 cotic properties. 

 A hemp - field, 



especially in a southern climate, when the hot 

 rays of the sun are acting upon it, has a pe- 

 culiar odour, which often produces, in persons 

 who remain any length of time in it, headache 

 and giddiness. This probably arises from 

 the volatile narcotic principle being evaporated 

 and suspended in the surrounding atmosphere, 

 and is consequently inhaled, and produces its 

 specific efiect. The quantity of this nar- 

 cotic principle, which is of a resinous cha- 

 racter, is much greater in the plant when 

 grown in hot countries than it is in colder 

 regions ; but the fibre is not so good, and is, 



Fig. 3. — Orobanche ramosa. 



