the Trade. Its address is Duke Street, E.C.2, and it is under 

 its auspices that this book is published. 



The key numbers printed in the dictionary, after the descrip- 

 tions of the best known instruments, represent firms who either 

 manufacture or factor such instruments. A list of the key num- 

 bers is given below, with the names and addresses of the firms 

 they refer to. 



LIST OF MEMBERS. 



1. ALDIS BROS., Messrs., Sare Hole Road, Sparkhill, Birming- 



ham. 



2. BAKER, CHARLES, 244, High Holborn, London, W.C.I 



3. BECK, R. & J., LTD., 68, Cornhill, London, .0.3. 



4. CAMBRIDGE SCIENTIFIC INSTRUMENT Co., LTD., THE, 



Chesterton Road, Cambridge. 



5. CASARTELLI, JOSEPH, & SON, Messrs., 43, Market Street, 



Manchester. 



6. CASELLA, C. F., & Co., LTD., Wansey Street Works, 



Walworth, London, S.E.ij. 



7. CHANCE BROS. & Co., LTD., Glass Works, Smethwick, 



Birmingham. 



8. DALLMEYER, J. H., LTD., Church End Works, Willesden, 



London, N.W.io. 



9. DOLLOND & Co. 44, Kirby Street, Hatton Garden, E.C.i. 



10. ENDACOTT SCIENTIFIC INSTRUMENT Co., Verulam Street, 



Gray's Inn Road, W.C.I. 



11. GRUBB, SIR HOWARD, & SONS, LTD., Rathmines, Dublin. 



12. UNITED KINGDOM OPTICAL Co., LTD., THE, White Hart 



Lane, Tottenham, London, N.iy. 



13. HEATH & Co., LTD., New Eltham Scientific Instrument 



Works, New Eltham, London, S.E.g. 



14. HILGER, ADAM, LTD., 75A, Camden Road, London, N.W.i. 



15. HUGHES & SON, LTD., HENRY, 59, Fenchurch Street, 



London, E.G. 3. 



16. KELVIN, BOTTOMLEY, & BAIRD, LTD., Cambridge Street, 



Glasgow. 



17. NEGRETTI & ZAMBRA, Messrs., Holborn Circus, London, 



E.C.i. 



18. OTTWAY & Co., LTD., W., Orion Works, Ealing, London, 



W. 5 . 



19. PYE & Co., W. G., Messrs., Granta Works, Montague Road, 



Cambridge. 



