Color-blindness

The subject of color-blindness has not 'et begun to receive in this country the ;tention it has abroad, but it certainly ught to, if Dr. B. J. Jeffries is riglit in ie conclusions expressed in an interestiug lecture delivered bofore the Boston Society of Arts. He has made a comparative examination of so many men that he feels assured in saying that one in twenty or twenty-five is colorblind, that is, either cannot discern green from red, or red from green, or violet froin either. This deficiency is, strange to say, moremarkedamong railroad employés than arnong the rest of the community - a circumstance wliose danger ia obvious, as upon the recognition of the color of lights depends often the safety of many livrs. The statistics are plentiful in Europe ; those Dr. Jeffries has obtained in this country are conflned to Boston, but there seems no doubt of the fact. The various tests to ascertain the existence of colorblindness are all discarded by Dr. Jeffries, excopt one originated by Prof. Holmgren, of Upsala, and first adopted in Swedcn, then by Norway and Kussia, and now by railroad managers all over Europe. It is as simple aa it is severe - rnatching oolored orsteds. Any man ■vvho has tried tliis little matter to oblige his wife or somebody else will appreciate the test. Oertainly vre must agres with Dr. JefMes that railroad and stenmboat men ought to pass an examination