Some kinds of nails, such as those used for defending the soles of coarse shoes, called hobnails, require a particular form of the head, which is made by the stroke of a die.

In turning from the smaller instruments in frequent use to the larger and more important machines, the economy arising from the increase of velocity becomes more striking.

He will also find that the high and independent spirit, which usually dwells in the breast of those who are deeply versed in scientific pursuits, is ill adapted for administrative appointments; and that even if successful, he must hear many things he disapproves, and raise no voice against them.

Perhaps it would be better for science, that all criticism should be avowed.

An object is frequently not seen, from not knowing how to see it, rather than from any defect of the organ of vision.

In mathematical science, more than in all others, it happens that truths which are at one period the most abstract, and apparently the most remote from all useful application, become in the next age the bases of profound physical inquiries, and in the succeeding one, perhaps, by proper simplification and reduction to tables, furnish their ready and daily aid to the artist and the sailor.

No person will deny that the highest degree of attainable accuracy is an object to be desired, and it is generally found that the last advances towards precision require a greater devotion of time, labour, and expense, than those which precede them.