^4 BOTH SIDES OF TEE BLUE GLASS QUESTION. 



.asserted that lunatics are greatl}^ affected by being placed in different col- 

 ored rooms. Eed light, Dr. Ponza says, removes feelings of depression, 

 blue induces calmness, and by violet light a crazy person was in one day 



■eured. 



"It is a thoroughly demonstrated fact that light is an important vital 

 stimulant; and that, if its operation be excluded, the development of the 

 healthy bodily structure is arrested. Naturalists tell us that in the absence 

 of light the transformation of a tadpole into a frog is stopped, and the rep- 

 tile remains a tadpole. Plants in darkness become blanched and stunted in 

 o-rowth • the process of fixing the carbon in their tissues is arrested, a mod- 

 ification of the coloring principle takes place, and they appear white 

 instead of o-reen. The sad effects of deprivation of sunlight are especially 

 observable among those who live in crowded alleys or cellars, or who work 

 in mines where the light of the sun seldom or never penetrates. The total 

 exclusion of the sun's beams produces an impoverished and disordered 

 state of the blood, emaciation, muscular debility, and the diseases due to 

 imperfect nutrition. 



"On the other hand, it is known that for certain purposes darkness or 

 •shaded light is advantageous to the bodily condition. Fowls, for instance, 

 may be fattened much more rapidly in the dark, and it would seem that the 

 absence of light exercises a very great influence over the power possessed 

 by food in increasing the size of animals. It likewise seems to exercise a 

 rsoothino- and quieting influence, increasing the disposition of animals to 

 take rest, making less food necessaiy, and causing them to store up more 

 nutriment in the form of fat and muscle. JSTow, if the organism to be 

 treated is subjected to light, all of which is filtered through blue violet glass, 

 then as we have previously demonstrated, it is in light which is consider- 

 ably shaded. And very probably to this cause — and not at all to the pecu- 

 liar hue of the light — is to be attributed the quieting influence on neYvous 

 and insane people which Dr. Ponza has remarked. 



"But Gen. Pleasonton does not use blue-violet glass alone. On the con- 

 trary, he employs a combination of blue light and pure sunlight, the latter 

 very much preponderating. In his grapery, for example, only every eighth 

 row of panes is blue. The mingled light consequently is merely pure sun- 

 light very slightly shaded, and the animal or plant exposed simply takes 

 a sun bath — the solarium of the ancients, who, knowing the vivifying influ- 

 ence of the sunbeams, had terraces built on the tops of their houses so that 

 they might bask in them. This sun treatment is now frequently recom- 

 mended by physicians for nervous diseases. Dr. Hammond, in one of his 

 lectures, says: 'In convalescence from almost all diseases, it acts, unless 

 too intense or too long continued, as a most healthful stimulant, both to 

 the nervous and phj^sical systems. * * * The delirium and weakness, 

 by no means seldom met with in convalescents kept in darkness, disappear 

 like mao-ic when the rays of the sun are allowed to enter the chamber.' 



"It is hardly necessary to add that in our opinion the use of blue glass, 

 as advocated by G-en. Pleasonton, is devoid of benefit." 



