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Thave likewife at this time (landing before a Micro- 
fcope, a (mall Portion of the Bone of an Ox» in which 
may evidently be (een the VelTels, which proceed 
from the Bone, and compofe what is called the Perio-' 
fteum, as likewife the Openings of thefe Veflels; the 
reafon of whofe appearing (b clearly is, as 1 imagine, 
that they are filled with the Medullary Oil, 
I take this Opportunity of informing you, that the 
Iron Crofs, which is fuppofed to have flood upon the 
Steeple of the Nevv-Church here about two hundred 
Years, having been lately taken down to be repair’d, 
1 was informed by a certain Foreign Gentleman, that a 
piece of Iron, that has flood for a long time in one 
Situation, would thereby acquire a Magnetick duality. 
Upon which I defir’d a Workman to procure me a piece 
of that Crofs, who accordingly brought me a bit of it, 
of about a Span long, and a quarter of an Irch thick, 
which I apply’d both to a working Needle, and the 
Needle of the Compafs, but without any EfFe<5t upon 
one or the other. 
Some time after, the fame Workman brought me 
Ibme other pieces, looking like rufly Iron, which he 
had broken off from the bottom of the Crofs, where 
it had been faflen’d by four crofs pieces bound 
down with Iron, to an ered piece of Timber nine 
Inches fquare, and cover’d with Lead in fuch a man- 
ner, that no wet could get to it. 
This feeming rufly Iron w^ould take up feveral 
Needles hanging by one another, and appear’d to have 
a flronger Magnetick Virtue than two Loadflones, 
- which I had then in the Houfe j and was fo hard, 
that no File would touch it. I gave one of the 
greatefl pieces to a Knifcgrinder, to grind it for me, 
who was a long time about it, and complain’d that it 
was harder than Steel. 
The 
