that it decreased as the square of the distance.
Alhazen determined correctly the relation between the velocities, spaces, and times of falling bodies.
The University of Cordova was the intellectual center of Europe in his day. The Khalif Alkamen's library was so large that its catalogue filled 40 volumes.
The people of Cordova could walk paved streets at night 10 miles in a straight line, by the light of public lamps, when London and Paris were dark and dismal mud-holes.
Galileo, born 1564, considered the subject of acceleration of force, and determined the relation between the spaces of descent and the times.
He used inclined planes, by the aid of which he conveniently diminished the velocity without changing the nature of the result.
The first boring-tool may be assumed to have been an awl of some kind.
Pliny states that Daedalus invented the gimlet, — 1240 B. C. It was destitute of a screw-point, but it may have had a hollow pod, and a cross-head forming a han
as of country at various times.
The uniformity of the Roman system was lost when they abandoned their provinces, but as the intellectual center still remained in the South the nations again gave in their adherence.
By an edict of Charles IX.
in 1564, the beginning of the year was ordered in France, at January the first.
The change was not made in England till a much later period, and is far from invariable even now in that country.
In the time of Pope Gregory XIII., A. D. 1582, the calendeen obliged to choose another mode of assassinating him. The carriage of Louis XIV.
of France, 1643, was suspended from springs.
The first state coach in England was that of Elizabeth.
Stage wagons were introduced into England in 1564, and coaches for hire plied in London in 1625.
Stage coaches were introduced into England by Jethro Tull, about 1750, and were employed to carry the mail in 1784.
Before this time it was carried on horseback.
See vehicles for lis
ered by Ptolemy Philadelphus in the college of Alexandria.
He even authorized the vivisection of criminals condemned to death.
Herophilus of Cos was among the first of the professors in this great school of medicine.
The practice of dissection was very repugnant to the prejudices of the Egyptians, where to touch a corpse was defilement, as we see it also to have been among the Hebrews, who became habituated to many of the Egyptian modes of thought.
Vesalius, born at Brussels 1514, died 1564, was among the most noted of the school of modern anatomists who have pursued the study of dissection.
His distinguished professional career was terminated by an unfortunate affair, which turned out to be a vivisection, as the supposed cadaver proved to be living.
The relatives who had granted the dissection denounced Vesalius to the Inquisition, who would have burned him but that Philip II.
stepped in and had the sentence commuted to a pilgrimage to Jerusalem.
ils known as lead-pencils is made from graphite, otherwise known as plumbago or blacklead. The latter two names are misnomers, as no portion of lead enters into its composition.
Graphite is a soft variety of carbon, sometimes containing a small proportion of iron.
It is found in many parts of the world, but few localities yield it of sufficient purity for making pencils.
For many years the best obtainable was from the mine of Borrowdale, Cumberland, England, discovered in 1564.
It was locally known as wad. This mine gave England the monopoly of the finest quality of pencils, and the amount taken from the mines yearly was strictly limited in order to keep up the price.
The annual product was valued at £ 40,000. This source of supply eventually failed, but the loss was scarcely felt, as a number of other mines had been discovered in various parts of the world.
The ancients drew lines and letters with leaden styles, and afterward an alloy of lead an tin was used.