Research on some Standards of Light 



503 



such results as had already been obtained. It is hoped that those who 

 are interested in photometric work will, by their advice and criticism, 

 help to bring the research to a satisfactory close. 



In concluding, may I be allowed to express my gratitude to the 

 managers of the Royal Institution for placing the splendid resources 

 of the Davy-Faraday Laboratory at my disposal, as well as for generousty 

 defraying the necessarily heavy expenses incurred by the present work. 



My thanks are also due to Messrs. Johnson, Matthey & Co., who 

 most kindly lent the platinum employed. 



