Investigation on the Chemical Nature of Wax. 217 



lO*, and read, by verniers, to one minute. The numbering 

 of the graduation commences at each extremity of the hori- 

 zontal diameter, and extends to 180°. The needle is three 

 inches and a half long, and is enclosed (together with its sup- 

 ports) in a rectangular wooden box with glazed sides. The 

 microscopes by which its position is observed carry each a 

 line in the focus, in the direction of the radius of the circle; 

 and the position of these lines is adjusted by the same means 

 as those employed in the former adjustment. 



The plane of the instrument being made to coincide with 

 the magnetic meridian, and facing the east, the deflecting mag- 

 net is to be fixed on its support at a given distance, with its 

 north pole towards the needle ; and the angles of position of 

 the deflected needle, <z 1 and a 2 , with its north pole towards the 

 north and towards the south, respectively, are to be observed. 

 The deflecting magnet is then to be reversed on its supports, 

 so as to have its north pole turned from the needle, its distance 

 being unchanged. Then a 3 and a 4 being the corresponding 

 angles of position, the magnetic inclination is 



A 1 / 



0= 7 («i + « 2 + a 3 + a d'> 

 and the angle of deflection is 



The observations are to be repeated with the face of the in- 

 strument towards the west, and will give new values of and 

 u, which are to be combined with the former. We have only 

 to observe that, in this latter case, the arithmetical mean of 

 the four observed angles is the supplement of the inclination, 

 instead of the inclination itself. 



XXXIII. An Investigation on the Chemical Nature of Wax. 

 By Benjamin Collins Brodie, Esq.* 



I. On Cerotic Acid, a new Acid contained in Beei-Wax. 



IN the summer of 1845, while studying at Giessen, in the 

 laboratory of Professor von Liebig, I undertook, at the 

 request of that distinguished chemist, the analysis of certain 

 waxes which were the results of an experiment made by M. 

 Gundlach of Cassel, of feeding bees upon different kinds of 

 sugar. It is not my intention to give those analyses here, and 

 I mention them now only for the purpose of stating that it 

 was this circumstance which first turned my attention to the 

 inquiry of which I now offer the results to the Royal Society, 



* From the Philosophical Transactions, part i.; having been received by 

 the Royal Society March 2, and read March 30, 1848. 



Phil. Mag. S. S. Vol. 83. No. 221. Sept. 1848. Q 



