...photographic purposes becomes at once apparent. The extract from the memoir referred to is as follows : — "The steady and equable light evolved by magnesium wire burning in the air, and die immense chemical action thus produced, render this source of light valuable as a simple means of...

...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. The extract from the memoit 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 out measurement of light. . . . The combustion of magnesium constitutes...

...photographic purposes becomes at once apparent. The extract from the memoir referred to is as follows : — "The steady and equable light evolved by magnesium...produced, render this source of light valuable as a 'mple means of obtaining a given amount of illumination oressed in terms of our measurement of light...

...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...of light valuable as a simple means of obtaining a giveu amount of chemical illumination, and that the combustion of this metal constitutes so definite...

...becomes at once apparent. In the memoirs published iu the above year it is stated that the steady awl equable light evolved by magnesium wire burning in the air, and the immense chemical ¿L-tiou thus produced, render this source of light valuable as a simple meiins of obtaining a given...

...ray e for photographic purposes becomes apparent. Professors Bunsen and Iloscoe say in their memoir: "The steady and equable light evolved by magnesium...thus produced, render this source of light valuable asa simpler means of obtaining a given amount of illumination expressed in terms of our measurement...

...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...

...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...action thus produced, render this source of light vaiuable as a simple means of obtaining a given amount of chemical illumination ; and that the combustion...

...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...