ALEXANDER GRAHAM BELL (1847 - 1922) American inventor of the telephone, formed the Bell Telephone Company, and established the Volta Laboratory which produced numerous related inventions and improvements on existing technology. Scarce, very fine content T.L.S. "Alexander Graham Bell ," 2pp., 4to, on stationery imprinted with his address in Washington, D.C., January 25, 1912, to Edwin A. Elsbach in San Francisco about marriage practices among young deaf persons that can decrease their handing down their defect to their offspring. He explains: "...A great deal can be done to minimise the effects of heredity in afflicted families, by giving such information regarding the results of marriages as to lead afflicted persons to choose partners in life who would lessen their tendency to produce afflicted children. There is always a strong tendency in offspring to revert to the normal type of the race; and if marriages are so contracted that the tendency to the inheritance of the defect exists in the family of one of the partners, the tendency to inheritance is diluted, so to speak, by the influence of the other, if he belongs to a family which is free from the defect. This is especially true when the partners in marriage are very far apart in blood. A defective American would have less tendency to reproduce the defect, by marriage with a foreigner of a different race. The further apart in blood the marriage partners are, the greater the tendency in the offspring to revert to the normal type of the race. Defective persons should especially, be careful to avoid marrying blood relations. This class of union tends to increase, the offspring, the family peculiarities, whatever they may be. Where a defective strain exists the defect is more liable to be increased, than in cases where there are no common ancestors. I send by separate mail, a copy of my paper entitled 'Marriage, an Address to the Deaf', in which I try to explain to young deaf persons those conditions of marriage that would be liable to increase any tendency they may have to hand down their defect to their offspring, and those conditions that would lessen the tendency... ". A rarely encountered content letter of Bell on a highly controversial subject at the time. Creases at folds, otherwise in very good condition. With original envelope. $3,500-4,500