...becomes at once apparent. Professor Bunsen and the speaker state, in the memoir above referred to, that " the steady and equable light evolved by magnesium...and that the combustion of this metal constitutes so definite and simple a source of light for the purpose of photochemical measurement, that the wide...

...purposes becomes at once apparent. Professor Bunsen and the speaker state in the memoir above referred to, that, "the steady and equable light evolved by magnesium...and that the combustion of this metal constitutes so definite and simple a source of light for the purpose of photo-chemical measurement, that the wide...

...purposes becomes at once apparent. Professor Bunsen and the speaker state in the memoir above referred to, that, "the steady and equable light evolved by magnesium...and that the combustion of this metal constitutes so definite and simple a source of light for the purpose of photo-chemical measurement, that the wide...

...photographic purposes becomes at once apparent. The extract from the memoir referred to is as follows : — " The steady and equable light evolved by magnesium...valuable as a simple means of obtaining a given amount of illumination expressed in terms of our measurement of light. .... The combustion of magnesium constitutes...

...photographic purposes becomes at once apparent. In the memoirs published in the above year it is stated that the steady and equable light evolved by magnesium...light valuable as a simple means of obtaining a given quantity of chemical illumination, and that the combustion of this metal constitutes so definite and...