BLIND 713 and also the fine particles of dust that are blown into the eyes, are causes which are very fruit- ful in producing ophthalmia in northern Africa. Again, as we approach the polar regions, where snow and icehergs reflect the sun's rays, the proportion of the blind increases. The follow- ing tahle, taken from the work of a blind author, W. Hanks Levy (" Blindness and the Blind," London, 1872), of blind persons in Eng- land and Wales, shows the proportion as to sex, and the tendency of increase of years to produce loss of sight : AGES. Milei. Female*. 619 510 896 675 " 20 " 80 936 632 " 80 " 40 1057 678 " 40 " 60 1.823 836 " 60 " 60 1,291 1,054 " 60 " 70 1.611 1,601 " 70 " 80 1,674 1,860 " 80 " 90 770 1,064 " 90 " 100 .. 63 183 (Jpward of 100 2 4 Total... 10,247 11.103 This table exhibits a great preponderance in the proportion of the female over the male blind who are more than 60 years of age, and a preponderance of the males below that age. A comparison of the proportion of male to female blind in the United States does not show precisely the same results, as will be seen from the following table prepared from the census of 1870: AGES. Mile. Female. 18 20 126 115 5 " 10 867 299 10 " 20 1,218 1,195 20 " 80 1078 681 80 " 40 1,109 648 40 " 51) . . 1292 683 50 " 60 1.256 746 60 " 70 .... 1,880 988 70 u 80 1148 1097 80 " 90 534 618 90 " 100 93 181 Upward of 101) . 16 25 Total. . . . 9.610 7.826 It is thus seen that about half of the blind in the United States are over 48 years of age. In all countries the number of males among the blind exceeds that of females, the excess being mostly caused by accidents, to which the for- mer are more exposed. It may be remarked that caution is required in forming conclusions from these tables. They have their value, but other facts must be weighed with them. One practical conclusion is gathered from the last table by Mr. Chapin of Philadelphia, which is that "if the adult blind were provided with instruction and employment in handicrafts in separate institutions, it would be practicable to receive and educate all the younger blind in the country over 10 years of age." Observation would indicate that the blind as a class have less vitality than those who have their sight, and statistics confirm this opinion. This want of vitality is doubtless one cause of blindness; but again, much of their want of vitality is in consequence of their being blind, which causes them to lead more sedentary lives than they otherwise would. As Dr. Howe remarks, " There are many who are not born blind, who are born to become blind." From statistics embraced in a report of the Boston institution, gathered from seven American state institu- tions, the director makes the following note: "Of the number of persons admitted to the above-mentioned institutions between the ages of 10 and 14, the number that was surviving in 1859 was 8'6 per cent, less, according to the Massachusetts life table, than the number that should then be surviving. Of the number ad- mitted during the three years of 1838-'40, from which the average time elapsing to the middle of 1859 was 20 years, the number that survived in 1859 was 12'3 per cent, less than the num- ber that should have survived." The number of blind in the world cannot be stated with any great degree of exactness. In the United States and in most of the countries of Europe, how- ever, the number is known from census returns. In other countries the number has been esti- mated by various travellers and writers, and from a comparison of data it is believed that a pretty near approximation has been reached. The table on the next page, compiled from the United States census of 1870, contains a con- siderably larger number than was shown by that of 1860, giving reason to believe that the latter census was imperfect. The following is a table of the blind in Europe, the number in Russia, Austria, Spain, Portugal, Italy, Greece, and Turkey in Europe being estimated; but the attention given to the subject in most of these countries makes it probable that the es- timates are pretty nearly correct : COUNTRIES. England and Wales.., Scotland Ireland Russia in Europe Sweden Norway Denmark Germany Austria Switzerland Holland Belgium France Spain Portugal Greece and Ionian Isle: Turkey In Europe Total. Population. No. of blind. Proportion 20.070.000 8,060,000 6.8011,000 64,000,0(10 8.610,000 1,490.000 1,800,000 48.000,000 88.000.000 2.510.000 8.809,000 4.580,000 88.0110,000 16.000.000 8,600,000 1,500,000 18,000,000 25S.iill9.WKt 19.852 2,820 6,S79 70,000 2,586 8,759 1.200 26500 88.0110 1,790 1,990 8.675 40,500 20,000 4,500 1.900 16,250 255,651 1 to 1,087 1,086 843 900 1.419 540 1,528 1,620 1.000 1,400 1.668 800 800 800 800 The above computation gives as the average proportion of the blind to the whole of the population of Europe, 1 in 1,094. It has been estimated that in China alone, with a population of about 400,000,000, there are at least 1,000,- 000 blind persons, and that there are in India more than 350,000. These estimates are made
