FOREIGN G0RRE8P0NDENCE. 757 



Messrs. Trelat and Gariel advocate that school-rooms shoiiid be lighted "bi- 

 laterally," cot from the centre, and thus flood the eye completely with light 

 — incompleteness in this respect producing nearsightedness, Michelet, 

 though poetically, has not the less accurately observed; the eye is a human 

 flower, which has want of sun-light, as other flowers, to prevent etiolation 

 and languishing. M. Dally, on the subject of the physiological aspects of 

 education, asks. Are we right to have a common dietary for children of the 

 establishment, when some of them have a predisposition for certain diseases 

 that an appropriate regimen could prevent ? He also disapproves of those 

 systems of education, which replace, at the commencement of the child's 

 cerebral life, impressions, sensations and object lessons for the abstractions 

 of grammar, dead languages, &c. 



The influence of colored light on plants and animals has lately occupied 

 much attention. It is difficalt at first to comprehend how the action of light 

 can. affect an invalid. M. Fano states that he has completely cured persis- 

 tent headache by his patient employing yellow glass spectacles. The 

 afflicted on attempting to read or write only augmented the headache, yet 

 as some kinds of intellectual work did not produce fatigue, M. Fano con- 

 cluded that the pain arose from the action of the retina on a morbid state 

 of the nervous centres. He decided to change the conditions of perception 

 for the retina, by no longer exciting it by the ordinary rays ; he employed 

 glass to produce only yellow rays ; the pain diminished, and by continuing 

 the same glasses, ultimately disappeared. M. Fano also obtained satisfactory 

 re^sults in certain cases, by the use of red, violet and other colored glass 

 one person being sensible to blue, another to rose, following constitution. 

 There are harmonies which delight the ear, why not colors to charm the 

 eye, and calm also its nervous system? 



Science, in point of novelties, keeps up with the spirit of the age. We 

 have had hygrometric or barometric flowers, which changed color, follow- 

 ing the humidity or dryness of the air; at present wo have luminous flow- 

 ers, that it sufiices only to expose to the sun, to observe them afterwards 

 becoming phosphorescent iu obscuritj'. The flowers are prepared with 

 sulphurets of calcium, strontium, &c., compounds known as artificial phos- 

 phorus. Messrs. Dagron and Gisclon have produced "sympathetic pipes.' 

 They can "color" a meerschaum the most beautiful chocolate in five minutes 

 by tinting the bowl with a solution of ether and alcohol, to which essence 

 of roses, camphor, nitrate of silver, &c., are joined, so that any image or 

 superscription painted on the pipe will gradually come out, like the im- 

 pression of a photograph, under the influence of the light or the heat of the 

 pipe. You can have your own portrait, or that of a friena, your dog or horse 

 sketched on the pipe, as the likeness will appear on exposure to the air. It 

 is well to remember, the metamorphosis once accomplished, is permanent. 



Lavoisier demonstrated that a diamond consisted only of carbon, by 



