( 304 ) 



In order to prepare the urea derivative, the cinnamide is dissolved 

 in eight times its weight of 96 pCt. alcohol, and when cooled to the 

 temperature of the room the hypochlorite solution, prepared according 

 to Graebe ^), is slowly dropped in, the free alkali being neutralised 

 Avith 2N hydrochloric acid immediately before use. For every 2 

 mols. of amide, 1 mol. of potassium hypochlorite should be added. 

 The liquid gets warm, and very soon a crystalline mass composed 

 of very slender needles is deposited. After a few hours the mass is 

 collected at the pump ; this does not go very readily on account of 

 the fine state of division. The yellowish mass is treated with hot 

 alcohol and then washed with water. A fairly pure urea derivative 

 is thus obtained (m. p. about 218). By recrystallisation once or twice 

 from glacial acetic acid it is obtained pure in needles (m. p. 225 — 226). 



0,1733 grm. yielded 0,0894 grm. H,0 and 0,4682 grm. CO, 

 0,1654 „ „ 0,1863 „ „ „ 0,4467 „ „ 



0,1654 „ „ 13,9 CC.N at 19^° and 765 m.M. 



Found 73,68 5,78 



pCt. C pCt. H 9,70 pCt. N 



73,66 5,85 



Theory C,3H,,N,0,: 73,95 pCt. C 5,51 pCt. H 9,59 pCt. N 

 The compound is insoluble at a low temperature in water, ligroin, 

 alcohol, methyl alcohol, ether, carbon disulphide and benzene; at the 

 boiling temperature slightly soluble in alcohol and benzene and freely 

 so in glacial acetic acid, chloroform and acetone. It is insoluble in 

 alkalis or acids. 



Chemical Laboratory, Technical High School, Delft. 



Astronomy. "Mutual occultations and eclipses of the satellites of 

 Jupiter in 1908. By Prof. J. A. C. Oudemans. 



(Communicated in the meeting of September 29, 1906). 



N.B. In the present communication the four satellites of Jupiter, known 

 since 1608, have been denoted by I, II, HI and IV in accordance 

 with their mean distances from the planet. The further letters n and 

 f indicate whether the satellite is tiear or far, i.e. whether it is in 

 that half of the orbit which is nearest to or furthest from the Earth. 

 The jovicentric longitudes as well as the geocentric amplitudes are 

 counted in "signs" and "degrees", the latter beginning from the superior 



1) Ber. 35, 2753. 



