70 



^42 H35 0-2 and EcHiRETiN^Css H28 O2, all of wliicli are obtained 

 from the dried petrolenm-extract by means of boiling alcohol. 

 Echitin is an indifferent body, crystallising in delicate white 

 leaflets ; Echitein is also indifferent and ciystalline ; Echiretin is 

 resinous and closely i-esembles I'esins, obtained by Heintz from the 

 milky juices of Brosimum (Galactodendron) utile and of Taberna- 

 montana utilis.] 



Draii'OU\S-l)l()0(l. Exudation of different plants, viz.: — Calamus 

 Rotang and some other s})ecies, Da^monorops Draco, Dracaena 

 Draco, and Pterocarpus Draco. Dark red-brown, when piilverised 

 carmine-red, without taste or smell, readily soluble in alcohol with 

 red coloiir, also more or less completely in ether, oils, and alkalies, 

 fuses at 210° and is destroyed in higher temperatures. The puii- 

 fied resin is composed according to the formula C40 Hoi Og . 



DulC'aiHiirill = Ces H50NO00. Alkaloid, foimd besides solanin, 

 in the twigs of the bitter-sweet (Solanum Dulcamara). To pre- 

 pare it, exhaust with alcohol of 80%, press, mix the tincture with 

 water, distil off the alcohol completely, filter the remaining liquid, 

 throw down with tannic acid, mix the washed deposit with newly- 

 precipitated hydrate of lead oxyd, dry, triturate, draw out with 

 alcohol of 90%, and let the tincture evaporate. — Pale-yellow, 

 translucid, resinoiis, brittle, permanent mass, when pulverised 

 white with a tinge of yellow; without smell, evolving the odour 

 of fresh bitter-sweet when moistened with alcohol or water and 

 warmed; tastes at fir3t very bitter, afterwai-ds lastingly sweet. 

 When heated to 100° the D., dried at the air, loses 8% of Avater, 

 up to 120° it imdergoes no further diminution of weight, but 

 becomes a little sticky, at 165° it softens, aboA'e 200° it liquifies, 

 but then already partially decomposed, by more heat it is reduced 

 to coal, while emitting a very faint horny odoin- and evolving 

 vapours of acid reaction. Water dissolves of the D. only ^/lors 

 its own weight; the solution smells and tastes slighty like bitter- 

 sweet, is of neutral reaction, is precipitated white by tannic acid 

 not altered by other reagents. Alcohol of 90% dissolves Yio, when 

 warm considerably more; the solution has a faintly alkaline re- 

 action and is precipitable by the chlorides of platinum and of 

 mercury. Ether dissolves ^/i44o. In liquor of ammonia it swells 

 up like a jelly without dissolving. 



[According to the latest researches of Dr. Geissler, the Dulca- 

 marin, prepared as above, is not pure. To purify it, dissolve in 

 water, allow to stand for some time, add to the filtrate acetate of 

 lead, filter, wash the precipitate, suspend in alcohol and decomjoose 

 with siilphuret of hydrogen. Evaporate the filtered liquid, dis- 

 solve the remnant in alcohol and evaporate to dryness. The re- 

 maining jnn-e Dxilcamarin has the composition C44 H34 O20 and 

 ])ehaves as a glucosid, separating into Dulcamaritin=:C32 H26 O12 



