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16 I have oberved the ame Proportion, of their Diameters to that of the Sun, that I publihed to the World in my Book of The Appearances of Saturn: namely, the Diameter of the Ring round Saturn is to that of the Sun as 11 as to 37; that of Saturn himelf about 5 to 37; that of Jupiter as 2 to 11; that of Mars as to 1 to 166; of the Earth as 1 to 111; and of Venus as 1 to 84: to which I hall now add that of Mercury oberved by Hevelius in the Year 1661, but calculated by my elf, and found to be as 1 to 290.

If you would know the way that we came to this Knowledge of their Magnitudes, by knowing the Proportion of their Ditances from the Sun, and the Meaures of their Diameters, you may find it in the Book before mentioned: And I cannot yet ee any Reaon to make an Alteration in thoe I then ettled, altho’ I will not ay they are without their Faults. For I can’t yet be of their Mind, who think the Ue of Micrometers, as they call them, is beyond that of our