In Yorkshire "the collier of fifty is usually an aged man; he looks overstrained and stiffened by labour."[46] "But whilst both the child and the adult miner appear to enjoy excellent health, and to be remarkably free from disease, it nevertheless appears that their labour, at least that of the adult miner, is, in its general result, and in the extent to which it is pursued, of a character more severe than the constitution is properly able to bear. It is rare that a collier is able to follow his calling beyond the age of from forty to fifty, and then, unless he be fortunate enough to obtain some easier occupation, he sinks into a state of helpless dependence. Better habits with regard to temperance might diminish, but would not remove, this evil; and the existence of this fact, in despite of the general healthiness of the collier population, gives rise to the question whether, apart from all considerations of mental and moral improvement, a fatal mistake is not committed in employing children of tender years to the extent that their strength will bear, instead of giving opportunity, by short hours of labour, for the fuller and more perfect physical development which would better fit them to go through the severe labour of their after-life."[47] In the coal-fields of North Durham and Northumberland, Dr. Elliott states "that premature old age in appearance is common; men of thirty-five or forty years may often be taken for ten years older than they really are."[48] Mr. Thomas Greenhow, surgeon, Walker Colliery, North Durham, says "they have an aged aspect somewhat early in life."[49] Of the effect of employment in the coal-mines of the East of Scotland, in producing an early and irreparable deterioration of the physical condition, the sub-commissioner thus reports: "In a state of society such as has been described, the condition of the children may be easily imagined, and its baneful influence on the health cannot well be exaggerated; and I am informed by very competent authorities, that six months labour in the mines is sufficient to effect a very visible change in the physical condition of the children; and indeed it is scarcely possible to conceive of circumstances more calculated to sow the seeds of future disease, and, to borrow the language of the Instructions, to prevent the organs from being fully developed, to enfeeble and disorder their functions, and to subject the whole system to injury which cannot be repaired at any subsequent stage of life."[50] In the West of Scotland, Dr. Thompson, Ayr, says—"A collier at fifty generally has the appearance of a man ten years older than he is."[51]