December 30, 1922] 



NA TURE 



CROSS SLIDE 



PHOTO-MEASURING 



MICROMETER 



(Additional New Model) 



Full particulars of Photo - measuring 

 Micrometers post free on application to 



ADAM HILGER Ltd., 



75a Camden Road, London, N.W.I 



(Entrance : 24 Rochester Place — adjoining) 



Telephone Numbe.s: NORTH 1677-8. 

 Telegraphic Address : "SPHERICITY, PHONE, LONDON." 



If the bonuses just declared continue 

 uninterruptedly an assurance at 

 death will be doubled after 37 

 years and trebled after 55 years. 

 An assurance of £1,000 costs 

 £27 or £34 a year to men 

 aged 30 or 40 next birthday 

 respectively. 



Equitable Life 

 Assurance Society 



Mansion House Street, London, E.C.2. 



W. Palin Elderton, Actuary and Manager. 



No Shareholders No Commission 



REFRACTOMETERS 



J.W.ATHA&CO. 



8 SOUTHAMPTON ROW, 

 LONDON, W.C.I. 



