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"There used to be a blind mathematician in this section, and he was familiarly known as Blind Trull. If a boy attended his schools and did not develop a talent for mathematics it showed that there was no such talent in him. When everybody else in the State failed on a problem it was sent to Blind Trull, and he got problems from far and near. He went out on the streets of the village one Saturday to be with the boys and spend some leisure hours. They began firing problems at him, and finally he became a little worried at them and got up to leave. Turning back he said: "Now, that that you have been giving me problems, let me give you one. Can any of you tell me how to find the number of cubic inches in a thorn bush?" The crowd took it for a joke. "Why, it's easy enough," said Blind Trull. "Just stick the thorn bush down in a barrel partly filled with water and when you pull it out, the distance in the rise and fall of the water will give you the basis for a correct calculation."

Source: The Monroe Journal, published Dec 18, 1906

"The Monroe Enquirer says of the blind mathematician of whom we spoke one day last week as living in the southern part of this county: "The blind man referred to is Mr. Francis M. Trull, we suppose. He is a native of this county, and is well known here as a good mathematician and grammarian. Mr. Trull was educated at the Institution for the Deaf, Dumb, and Blind, at Raleigh.""

Source: The Charlotte Observer, published Mar 24, 1875

"Monroe, N.C., July 11, 1873.
Mr. Editor: To-day O. II. Dockery made a farcical harangue to the Radicals of Union County. His speech was after his usual style - bullying, fallacious, and demagogical. He admitted that the Radical Legislature of '68 and '69 had drained the State Treasury, and that its members had received large sums from Swepson (?) to vote for the appropriation to the W.N.C.R.R. and be offered no apology for the bribery. He tried to counter-balance the effect of this admission by showing that Judge Merrimon had received a large amount for drafting the "appropriation bill", but when it was alleged that that bill was now on file in the proper handwriting of our immaculate Governor, he made no reply at all. It was really rich to see Dockery cut off at the knees by a blind school teacher, Francis Trull, while Dockery was trying to prove that the Legislature of 1868, '69 and '70 did not receive as much per diem as the Legislature of '70-'1-'2. Dockery alleged that gold in '69 was worth $1.40, and that 40 per cent of $7.00 deducted from $7.00 left $4.20, and 10 per cent of $5.00 left $4.50; leaving a balance of 30 cents in gold in favor of the Radical Legislature. Trull told him 40 per cent discount off $5.00 left $4.54 - the amount received by the Conservative Legislature; leaving a difference in favor of the Conservative, of 46 cents. This calculation caused Dockery to lose his temper, and he ordered the blind man to get down, and said he would prove his proposition to be true yet, as it was not customary for him to be run over after that style; but he didn't do it."

Source: The Semi Weekly Eagle, published Jul 17, 1872