154 DR. LOWIG ON THE ESSENTIAL OIL 



M. Pagenstuher, an apothecary in Berne, had ah-eady drawn attention 

 to the oil and distilled water of the blossoms of Spircea Ulmaria in a 

 treatise which may be found in Buchner's Repertorium, vol. xLix.p.337. 

 He there describes exactly almost all the combinations which are the 

 subject of this Memoir; and had he made analyses of the elements with 

 only a few substances, the real nature, not only of the oil itself, but also 

 several decompositions and recompositions which it experiences would 

 not then have escaped him. 



M. Pagenstuher had the kindness to give me the oil for all the in- 

 vestigations, and also to communicate to me his observations made 

 up to that time. All his experiments which were of any importance 

 on the present subject are incorporated into this Memoir, so that in 

 many respects the present work may be considered as undertaken con- 

 jointly with M. Pagenstuher. To facilitate the general view of the fol- 

 lowing experiments, a few of the leading results may be first stated. 



The oil of the blossoms of the Spircea Ulmaria is a hydracid ; it con- 

 sists of one eq. of a radical = C12 HS 4, and one eq. of hydrogen, 

 which uniting with the radical forms an acid. If the hydrogen, which 

 by uniting with the radical forms the acid, be oxidized by nitric acid, 4 

 additional eqs. of oxygen are taken up by the radical, thus forming the 

 oxyacid of the same radical. Instead of 1 eq. of hydrogen, the radical 

 can unite with 1 eq. of chlorine, bromine, iodine, or even of a metal. 

 These latter combinations are also formed when the hydracid is made 

 to act on metallic oxides. With ammonia, on the contrary, the hydracid 

 unites without undergoing any change. From these combinations the 

 following compounds result: 



C12 H5 04+ H 

 C12 H5 04+ CI 

 C12 H5 04-I- Br 

 C12 H5 04+ I 

 C12 H5 04+ P 

 C12 H5 04 + 04 

 (C 12 H 5 4+ H) + N H 3 or ammonia. 



The radical is designated by the name Spir^oyl, or for the conve- 

 nience of shortness Spiroil. Another name would have been chosen for 

 it liad not a similar nomenclature been already applied to another sub- 

 stance nearly allied to it. It is always doubtful policy to derive the 

 name of a vegetable principle from the plant in whiclr it is first disco- 

 vered, for generally with great probability the same body may be found 

 in other plants. Names which designate any principal peculiarity of the 

 substance are therefore in such cases always preferable. One of the pe- 

 culiarities of spiroil is its property of forming yellow compounds with 

 oxygen, and with the metals, alkalies, and earths ; a name therefore which 

 had reference to this quality would have been very suitable. A name 



