Kalia, PN

IACS Institutional Repository

TECHNIQUE FOR MAKING SCHUMANN-PUTES. BY P. N. KALIA, M.Sc., Research Scholar, Physics Department, Government Gllcge, Lahore. In our work with the vacuum spectrograph of this labow we have bad mnsidcrablc dificnlties with the photographic plates imported from Europe. The plates by the~~~selves may be of excellent quality but the long delay c a u 4  in using the111 on account of the time taken for transit, considerably reduces t l~e i r  eficiency. Thc lasting qualities of the pfates are aka impaired by the high tenlpetaturc and grcat hu111idity prevalent in India. And therefore unless a regular supply of imported plates is maintained it is unsafe to spend labur and tinle over an exposure w dependable plates in a vacuum spectrograph adjusted after many dificultis. Our own view, based m~ several pears' experience in this line is that the only satisfactory arrangement is to e&oy Schumann plates pared in the laboratory. The p d u r e  employed in their manufadwe is essentially the same as that described by Schumann but oertain rnodifiatims and precautions h m e  necewry due to I n d h  c l i n ~ k ,  in ordm to prod- a -ll). serviceable article. We are giving the process here h detail to k l p  workers who may atre to prepare them by tbernselws. Process. It is desirable to set apart a mom for makiig the plates, m e  which is ns fm from dust as possible, and provided with at least one ruby tight laatem. It is wt safe to resume tlmt the red light provided by en ordinary glass is quite suit*& and it is therefom advisable to examine it with a direct vision b d e  using it. Siutians of red dyes in water put in a glnss jar and nmmundhg ra electric letup will be found to be very useful, sincc the strength of tbc dye ir easily adjustable. It will be found mvcnient to cowt the wmking table with Pper as this provides a cleoller place thaa m y  otherwk bc nvsilnblc. 

TECHNIQUE FOR MAKING SCHUMANN-PLATES.

Abstract

Similar works

Full text

Available Versions

IACS Institutional Repository