This Workmen’s Compensation case involves disability allegedly caused by silicosis. The Board denied compensation on the finding that the employee’s ailment was asthmatic. The circuit court affirmed this order. The claimant has filed a very lengthy brief which covers many different questions. The only real issue before us is whether or not there was substantial evidence of probative value to sustain the Board’s finding of fact. See Blue Diamond Coal Co. v. Hensley, 314 Ky. 85, 234 S.W.2d 317.
The employee had worked for a number of years as a coal digger and loader. He quit work in June, 1948, because of breathing difficulties. The disability is not in question, and the proof was principally directed to the cause of it. Two doctors testified for the employee. In the opinion of one of them, he was suffering from silicosis. In the opinion of the other, the condition of his lungs indicated that such could *926have been his affliction. The first doctor s opinion was based upon certain hypothetical facts which did not exist, one being that the employee had spent several years operating a motor which would produce silica dust.
Two doctors also testified for the employer, and diagnosed the employee’s condition as having been caused by asthma, from which he had suffered since 1930.
All of the doctors agreed that silicosis is caused by long exposure to dust containing a substantial amount of free silica. The claimant was unable to show that in his place of work he had been exposed to such harmful dust. On the other hand, the employer’s proof tended to rebut this possibility.
The Board’s determination is supported by very substantial evidence. We know of no ground upon which we could reject such evidence and declare that the finding of fact was erroneous.
The judgment is,, affirmed.