power to mitigate the evils which he cannot altogether avoid. In this point of view Mr. Thackrah’s book deserves the most serious consideration of all classes. It is most satisfactory to know, upon Mr. Thackrah’s authority, that “in many of our occupations the injurious agents might be immediately removed or diminished.” For the convenience of his inquiry the writer before us divides society into five great classes, viz.--I. Operatives. II. Dealers. III. Master Manufacturers, and Merchants. IV. Men independent of business and labour. V. Professional Men.--The first section of operatives he sub-divides into--1, those whose employments are chiefly in the open air; 2, those whose employments are carried on in an atmosphere confined and impure; 3, those whose employments produce dust, odour, or gaseous exhalations; 4, those whose employments injure or annoy by acting on the skin; 5, those whose employments expose them to wet and steam; 6, those who are exposed to a high temperature, or great variations of temperature. When we state that in these six sub-divisions of the great class of operatives, Mr. Thackrah describes the peculiar effects of about two hundred different employments, it must be evident that we cannot attempt even to enumerate the occupations whose influence upon health is here noticed. To show, however, the interesting mode in which this inquiry is for the most part conducted, we subjoin an abridged extract, descriptive of the condition of the grinders and machine-makers of Sheffield:-- “Dr. Knight, in the North-of-England Medical Journal, states that the fork-grinders, who use a _dry_ grindstone, die at the ages of 28 or 32, while the table-knife grinders, who work on _wet_ stones, survive to between 40 and 50. Dr. K.’s paper very properly alludes to the combination of injurious agents and circumstances. It is not, merely the pernicious employment, but the want of sieve and ventilation in the apartments where the men now work,--the want, moreover, of that exercise in the open air which they formerly took in going to work and returning from it; and finally, the intemperance which results from their congregation, and still more from their desperation of life. It appears, that in 1822, ‘out of 2,500 grinders, there were not 35 who had arrived at the age of 50, and perhaps not double that number who had reached the age of 45; and out of more than 80 fork-grinders, exclusive of boys, it was reported that there was not a single individual 36 years old.’ The symptoms of the grinders’ disease are those of slow but certainly fatal consumption. The remedies judiciously recommended by Dr. Knight, are, 1st. Dusting the machinery, before the work commences: 2nd. Great reduction in the time of labour: 3rd. Use of wet stones as much as possible; 4th. Large flues to be laid on the floor for ventilation, and currents of air to be forced through them by the machines: 5th. Fork-grinding to be confined to criminals.