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miles.  But in practice it is short of half a mile.  the resistance of the Air to this bullet, when it first issues from the piece, amounts to 120 times its gravity.  Again an iron bullet of 24 [[superscript]] unclear [[/superscript]] made with a full charge of powder, has a velocity of 1650 feet in a second; and the amplitude, at 45°, according to Theory, = 16 miles; but, by experiment it was short of 3 miles.  The same is in much less velocities for a bullet 3/4 of an inch diam. fired at different elevations with a velocity of 400 feet p 1" did not at all answer common theory.  Likewise the elevations under 45 degrees are greater than those above, which, by theory, are equal.  And the vertex of the curve they describe is much nearer the point where they strike the ground, than to that from whence they were first discharged.  Also they were frequently driven to the right or left of the point directed to, by the action of some other force: the error was always uncertain & bore no ratio to the distance.  Universal Magaz. Vol XVII. p. 104. for September 1755.
[[underline]] "It is generally agreed among the chymists, that all colours arise from sulphurs, and that they differ, according to the different admixture of salts with these sulphurs. [[/underline]] the flowers of all plants abound in an essential oil or sulphur, to which their colours maybe rationally owing.  Though this oil should be the same substance in all, yet their varieties of colours may be accounted for from it; since, that one and the same oil ([[underline]] viz. [[/underline]] the essential oil of thyme) may be turned to all the colours that we find in the different flowers of plants.  The infusions of flowers, and of other parts of plants, become red on being mixed with acids, and green on being mixed with alkali's. from the sulphureousness of the vegetable.  See more at large Universal Mag. Vol XVII. p. 22. for July, 1755.

The reflexion of the light from the earth greatly rarifies the medium between her and the moon in conjunction, but in [[underline]] eclipses [[/underline]] of the moon, part of this space is made denser, so that the inequality of pressure is not so great upon the moon as at other times; ^ in consequence of which the motion of the moon must be [[underline]] retarded [[/underline]] by eclipses, and hence it is, that [[strikethrough]] the [[/strikethrough]] calculations from modern Tables will not agree with the observation of ancient eclipses; [[strikethrough]] and likewise [[/strikethrough]] ^ nor ancient Tables [[strikethrough]] will not [[/strikethrough]] answer for the present time; neither will any tables continue true for many ages, because, from these eclipses, we are continually gaining time of the moon, or to express it more accurately, The Solar time hereby is continually gaining upon the Luna^r time.  No other setalite can thus be apparently discerned, because they very rarely miss passing thro' the shadow of their primary, and thereby is included & reckoned into their periods, tho' unknown to the astronomical Observor.-- Eclipses of the sun seldom or at most reach but a very small spot upon the earth cannot so sensibly affect her in this respect, if at all sensible; so that it is peculiar to the moon alone, whose motions are the most irregular of all the Celestial bodies. Mr. Jones.
    The Astronomers finding that the times of lunar eclipses happened later in some ages ago than they ought by the present astronomical tables, are led to think the moon is continually accelerated, & some have gone so far as to compose tables for that supposed accelaration, to be added both for [[strikethrough]] former Ages [[/strikethrough]] past and future ages, of which, the latter is false, because it is a retardation, which they are not aware of.
[[underline]] Tycho Brahe [[/underline]] argued from Refraction against the solid orbs of Aristotle.  for if any such orbs had existed, the rays of the heavenly Bodies could not have passed thro' them to our sight but under several Refractions; which is contrary to observation.  
  But this argument has of late be^en carried much farther; even to prove that these rays are transmitted to us through a vacuum, or nearly such, because they suffer no refraction till they come very near the Earth's surface.  which conclusion is much too hasty; it being here taken for granted, without any proof, that the Air, strictly understood, is the refracting medium; whereas the pure air is perfectly pellucid, and by all that appears does neither [[underline]] reflect light [[/underline]] (*) nor refract it.  Water will do both; and the air near the
(*) Air does not [[underline]] reflect [[/underline]] light, because a space exhausted of air looks as bright or brighter than [[corner of page curled, obscuring any writing that may be present]] filled with air; whereas it [[unclear strikethrough]] ought to look dark.