Great Britain first gave legal recognition to the class of feeble-minded above the imbeciles in its Education Act of 1898, following a report of a departmental committee of its National Board of Education growing out of the inquiries of Francis Warner. This committee estimated the proportion of this class as approximately 1% of the elementary school population (_181_). In discussing the comparative estimates on the general and school populations I have already referred to the estimate of Tredgold based upon an elaborate analysis of the most extensive data ever collected,—that gathered by the British Royal Commission on the Care and Control of the Feeble-Minded. While the Commission's investigators enumerated 0.79% among the school as mentally defective, Tredgold's estimate based on his analysis of their report was that 0.83% of the school population in England and Wales were above the grade of imbecile but still feeble-minded (_204_, p. 157). The variability of the estimates collected by the Royal Commission from various cities probably indicates the subjective character of the standards of deficiency. They varied from an estimate of 0.24% of the elementary school population in Durham to 1.85% in Dublin (_204_, p. 159). The Commission says regarding estimates as to communities other than those reported by their medical investigator, for Newcastle the “number of feeble-minded children of school age” (morons) was 0.25%, for Leeds the estimate was 0.80%, for London 0.50% or 0.60%, for Bradford 0.50%, for Dublin about 1% and for Birmingham about 1% of the school population. Dr. Francis Warner's general estimate was 0.8%. We have thus variations in estimates from 0.25%, 0.5%, 0.80% to 1% and some 2% (_167_, p. 90). For the rural areas the estimates were generally less. A careful estimate has been made with a different method by Karl Pearson on the basis of a classification by teachers of school children in Great Britain into nine different classes each especially defined and extending from the imbecile to the genius. This distribution of the children was then fitted to the normal probability curve. On this basis Pearson estimated that 1.8% would fall in the “very dull group,” defined as having “a mind capable of holding only the simplest facts, and incapable of grasping or reasoning about the relationship between facts; the very dull group covers but extends somewhat further up than the mentally defective.” Lower down would be 0.1% in the imbecile group. He says further regarding this estimate: “It is deduced from three series covering between 4000 and 5000 cases, and the three separate results are in several accord. It will, I think, be possibly useful for other inquirers, and it endeavors to give quantitative expression to our verbal definitions of the intellectual categories” (_166_).[7]