32 Historical Sketch of Improvements in [July, 



and the fat oils, and very little soluble in the essential oils. (See 

 Ann. de Chim. et de Phys. xii. 113). 



3. Delphia. — This alkaline substance was detected in July, 

 1819, by MM. Lassaigne and Feneulle, in the seeds of the 

 delphinium staphysagria, or stavesacie, in which it exists united 

 to mahc acid. They obtained it from these seeds by the follow- 

 ing process : 



The seeds were cleaned, and reduced to a pulp : they were 

 then boiled in water, and the liquid was separated by the filter. 

 This liquid was boiled for some minutes with a quantity of pure 

 magnesia. The solid part of the mixture was then separated by 

 the filter, and digested in boiling alcohol. The alcohohc solu- 

 tion being evaporated left the delphia in a state of tolerable 

 purity. 



Delphia thus obtained is a white powder, having a crystalline 

 texture while moist, but becoming opaque by exposure to the 

 air. Its taste is very bitter and acrid. It is destitute of smell. 

 When heated, it melts, and assumes the appearance of liquid 

 wax ; on cooling, it becomes hard and brittle, like resin. At a 

 still higher temperature, it swells up, blackens, gives out a white 

 smoke with a peculiar odour, which takes fire in the air. It 

 leaves behind it a light charcoal, which burns without leaving 

 any residue. 



Cold water has little action on it, yet it must dissolve a small 

 quantity as it acquires an acrid taste. Alcohol and sulphuric 

 ether dissolve it with facility. The alcohohc solution gives a 

 green colour to syrup of violets, and restores the blue colour of 

 litmus reddened by vinegar. 



It unites with the acids, and forms neutral salts, which are 

 very soluble in water, and have a very acrid and bitter taste. 

 The alkalies precipitate the delphia from these salts in a white 

 jelly like alumina. 



Sulphate of Delphia does not crystallize ; but when exposed 

 to spontaneous evaporation, dries into a hard transparent mass 

 similai" to gum. It dissolves readily in water and alcohol. Its 

 solution has a bitter and acrid taste, which remains in the mouth 

 for several hours. When a concentrated solution of this salt is 

 acted on by a galvanic battery, the salt is decomposed, the sul- 

 phuric acid being deposited at the positive pole, and the delphia 

 at the negative pole in white flocks. When sulphate of morphia 

 is treated in the same way, it undergoes a similar decomposition, 

 but the morphia is deposited in distinct white needles. 



Nitrate of Delphia made by dissolving delphia in very weak 

 nitric acid is colourless. When concentrated, it assumes a yel- 

 low colour ; evaporated to dryness, it has the same colour, and 

 a crystalhne aspect. When this nitrate is treated with an excess 

 of acid, it is changed into a yellow matter, but httle soluble in 

 water. Boiling alcohol dissolves it with difficulty. Potash, 

 ammonia, or hme-water, added to this solution does not occasion 



