HORTICULTURE IN RELATION TO MEDICINE. 



61 



Red Rose petals . 

 Rhubarb root 

 Savin 



Stramonium plant 

 Wormwood 



2.200 lb. 

 20 tons. 

 25 cwt. 

 22 cwt. 

 1^ tons. 



Since that date the cultivation of peppermint, lavender, belladonna, 

 aconite, and rhubarb has largely increased, but no figures are available 

 relating to the amounts at present grown in this country. Some experi- 

 ments made in Canada and the Ignited States show that several of the 

 above plants cannot be successfully or profitably grown in the American 

 Continent. Peppermint, however, is now grown to an enormous extent 

 in the United States, and the oil is even imported into this country, 

 chiefly for purposes of confectionery, the English oil of peppermint being 

 mostly used for medicinal purposes. The English oils of peppermint and 

 lavender are still regarded as being of finer flavour than those of any 

 other country, and are exported to all parts of the world, and everywhere 

 obtain the highest price. As a rule English drugs command a higher 

 price than those grown elsewhere, with the single exception of rhubarb 

 root, which is always cheaper than that imported from China. The 

 reason of this is that no traveller has yet succeeded in bringing to Europe 

 roots or seeds of the plant which yields the finest rhubarb root of that 

 country. The species already brought from China, viz. Rheum palmulum 

 and its variety Tanguticum, R. Collinianum and R. officinale, all yield roots 

 differing in structure and markings from, and are less active than, the 

 finest Chinese root. The species cultivated in this country are Rheum 

 Rhaponticum and Rheum officinale, and the root is chiefly used by 

 herbalists and exported to the United States. 



The cultivation of medicinal plants on a wholesale scale is of com- 

 paratively recent date, certainly not earlier than the middle of the 

 eighteenth century, with the exception of lavender, which was apparently 

 cultivated in 1568 at Hitchin, that of peppermint having been begun in 

 1750 and that of rhubarb in 1777. The regular use in medicine of 

 aconite, henbane, and stramonium dates only from the experiments 

 made by Dr. Stoerck, of Vienna, about the year 1672, although their 

 properties were recognised some centuries earlier, except in the case of 

 belladonna, the first description of which as a distinct plant appeared in 

 the " Grand Herbier " published in Paris probably about 1504. 



Besides the plants enumerated in Mr. Squire's list, a few others are 

 grown to a lesser extent, including the squirting cucumber (Ecballium 

 Elaterium), wild lettuce (Lactuca virosa), and rosemary (Rosmarinus 

 officinalis). It has been found worth while even to cultivate foxglove 

 (Digitalis purpurea) and hemlock (Conium maculatum), for although 

 both plants are locally abundant, the cost of carriage by rail, and the delay 

 in delivery causing alteration in the active constituents of the plant by 

 heating, have shown that it is cheaper to grow them, and manufacture 

 preparations on the spot. In this way the plants can be chopped up and 

 ground by machinery, and the juice expressed by hydraulic pressure 

 within twenty minutes after the cart has brought them from the field 

 to the factory, and within forty minutes afterwards the juice can be 

 evaporated in steam -heated pans to a solid extract. 



