Page:Philosophical Transactions - Volume 003.djvu/105

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no other than this; I took Spectacles that had the largest Circles; close to the semi-circles, on the over-part, on both sides, I cut the bone; then, taking out the Glasses, I put black Spanish leather taper-wise into the emptied circles, which widen'd enough (together with the increasing wideness of the Leather,) took in my whole eye at the wider end; and presently saw the benefit through the lesser taper-end, by reading the smallest Prints that are, as if they had been a large and fair Character. I caus'd a Glover to sow them with a double-drawn stitch, that they might have an agreeable roundness, and exclude all rayes of light. So l colour'd the Leather with Ink, to take off the glittering. And this was all the trouble I had, besides the practice and patience in using them. Only, finding that the smaller the remote orifice was, the fairer and clearer the smaller Prints appear'd; and the wider that orifice was, the larger Object it took in, and so required the less motion of my hand and head in reading; I did therefore cut one of these Tapers a little wider and shorter than the other; and this wider I use for ordinary Prints, and the longer and smaller for smallest Prints: These without any trouble, as oft as I see need, or find ease in the change, I alter. l can only put the very end of my little finger into the orifice of the lesser, but the same finger somewhat deeper, yet not quite up to the first joynt, I can insert into the orifice of the wider. Sometimes I use one eye, sometimes another, for ease by the change; for you must expect that the visual rayes of both eyes will not meet for mutual assistance in reading, when they are thus far divided by Tubes of that length.

The lighter the stuff is, the less it will cumber. Remember alwayes to black the inside with some black that hath no lustre or glittering. And you should have the Tubes so moveable, that you may draw them longer or shorter, allowing also (as was newly intimated) the orrifice wider or narrower, as is found more helpful to them, that have need of them. To me it was not necessary, but I conceive it convenient, that Velvet or some gentle Leather should be fastned to the Tabulous part next the eyes, to shadow them from all the encompassing light.

I have already told you, that I found no benefit at all by any kind of Spectacle-glasses; but I have not tryed, what Glasses will

doe,