ox THE PERIOD OF THE VARIABLE STAR S AR.-E. 263 



Dealing- with these in the usual manner yields for S Aroc the 

 Elements of Variation : — 



2,415,021"- 6'- 4i'.3 



+ 10"- 50' 43"-624E 

 - o".oooo245E^ 



The secular term in the abo\e, 



o". 0000245 

 is the important fact, as it indicates that the period of S Arce is 

 slowly decreasing-. 



This decrease is 



o".OQC049 

 each revolution of the secondary star round the primary. 



At first sig-ht this may seem an inappreciably small quantity v 

 but in ten years a lagging each period of 



o".oooo49 

 will aggregate to a lateness of ten minutes on the scheduled time 

 of maximum, an amount readily discernible in a star so rapid in 

 its changes as S Arce. 



Further, although the secular diminution in period only 

 amounts to a decrease of five minutes in a thousand years, this in 

 the life history of a star is but a very small span. 



So that if the decrease in period of S Arce is a constantl}- 

 accelerating quantity, as it may possibly be, if it is due to the 

 action of a resisting medium, probably an extended but tenuous 

 atmosphere round the primary star, through which the secondary 

 star has to pass, then the end of the star as a binary system is not 

 remote. 



It is possible that the secular change in period is cyclical, 

 however, and that an increasing stage will follow on the diminu- 

 tive stage, which is at present in operation. 



The problem of the evolution and life history of a star is 

 internally bound up with the question of period, and it is because 

 of this that the present paper on the secular diminution of period 

 of S Arcs is submitted. 



POISONOUS NATURE OF KAMASSI WOOD.— 



The Kamassi tree, or South African boxwood {Gonioma Kamassi) 

 has been used in Lancashire at times for the manufacture of 

 shuttles, and symptoms of poisoning have occurred amongst the 

 men engaged in operating upon the wood. The latter was accor'd- 

 ingly submitted to chemical analysis, and Dr. \V. E. Dixon com- 

 municated to the Royal Society, at its meeting on the 19th Jan- 

 uary, the information that the wood contains about .07 per cent. 

 of an alkaloid belonging to the curare group. The physiologicaT 

 action of this alkaloid comprises paralysis of the nerve cells in the 

 brain and medulla, strychnine-like convulsions if injected into a 

 vein proceeding to the spinal cord, and paralysis of motor nerve 

 endings. The recorded cases of poisoning are believed to be due 

 to the effect of the substance in facilitating local reflexes of a 

 respiratory nature. 



