318 Mr. J. Hopkinson. [Feb. 14, 



Observations, &c. (continued). 



Observations faites au Cap Thordsen, Spitzberg. Tome II. 



Ease. 2-4. 4to. Stockholm 1887. 



The Meteorological Office, London. 

 Kiel : Commission zur Untersuchung der Dentschen Meere. 



Ergebnisse der Beobachtungsstationen. Jahrg. 1887. Heft 7-9. 



Obi. 4to. Berlin 1888. The Commission. 



London : Navy Medical Department. Statistical Report. 1887. 



8vo. London 1888. The Department. 



Stationery Office. Voyage of H.M.S. " Challenger." Report. 



Zoology. Yol. XXIX. Text and Plates. 3 vols. 4to. London 



1888. The Office. 



Lyme Regis : Rousdon Observatory. Observations. 4to. [Sheet.] 



1889. Mr. C. B. Peek. 



Manchester: Public Free Libraries. Annual Report. 1887-88. 



8vo. Manchester. The Committee. 



February 14, 1889. 

 Professor G. G. STOKES, D.C.L., President, in the Chair. 



The Presents received were laid on the table, and thanks ordered 

 for them. 



The following Papers were read : 



I. " Magnetisation of Iron at High Temperatures." (Preliminary 

 Notice.) By J. HOPKINSON, F.R.S. Received January 30, 

 1889. 



I have recently been making some determinations of the curves 

 of magnetisation of iron at varying temperatures up to that at 

 which the iron ceases to be magnetic. Although the experiments are 

 still progressing, some of the results are of sufficient interest to be 

 worth publishing briefly at once. 



The method of experiment was identical with that which I used 

 for a sample of nickel about a year ago. The temperatures are esti- 

 mated by the resistance of a copper secondary coil, and as there may 

 be some uncertainty as to what temperatures the several resistances 

 correspond with, I give in the curves which follow the resistance 

 observed as well as the temperature estimated. 



