1898.] of Iodine in Air at Atmospheric Pressure, etc. 47 



made a series of experiments on the same subject in which he 

 proves that bromine and iodine dissolve in air or oxygen under 

 high compression. He says, " L'lode se dissout egalement en 

 quantite sensible dans l'Oxygene, mais le phenomene n'est bien 

 visible qua partir de 100 atmospheres et dans des tubes de 5 milli- 

 metres de diametre an moins." 



The experiment exhibited would appear to show that one 

 atmosphere of pressure is sufficient to produce a sensible difference 

 of colour in the case of iodine vapour diffused in air as compared 

 with a vacuum ; and in the meantime as a lecture illustration the 

 experiment may be of some interest. 



(4) On the partitions of numbers which possess symmetrical 

 graphs. By Major MacMahon, Sc.D., F.R.S. 



[Printed in the Transactions, Vol. xvn. Part II.] 



