a Medium actually hot, and having its heat continually renewed by a fountain of heat.
12, How to estimate the solidity of the Body of Ice, or how strong is the mutual adhesion of its parts? and whether differing Degrees of Cold may not vary the Degree of the compactness of Ice. And our Author having proceeded as far as he was able towards the bringing the strength of Ice to some Estimate by several experiments, he communicateth the information, he could get about this matter among the Descriptions that are given us of Cold Regions: And then he relateth out of Sea-mens Journals, their Observations touching the insipidness of resolved Ice made of Sea-water; and the prodigious bigness of it, extending even to the height of two hundred and fourty Foot above water, and the length of above eight Leagues. To which he adds some promiscuous but very notable Observations concerning Ice, not so readily reducible to the foregoing Heads: videlicet, Of the blew Color of Rocky pieces of Ice; and the horrid noise made by the breaking of Ice, like that of Thunder and Earthquakes, together with a Consideration of the Cause, whence those loud Ruptures may proceed.
13, How Ice and Snow may be made to last long; and what Liquor dissolves Ice sooner than others, and in what proportion of quickness the solutions in the several Liquors are made, where occasion is offered to the Author, to examine, whether Motion will impart a heat to Ice? After which, he relates an Experiment of Heating a Cold Liquor with Ice, made by himself in the presence of a Great and Learned Nobleman, and his Lady, who found the Glass wherein the Liquor was, so hot that they could not endure to hold it in their Hands. Next, it is examined, whether the effects of Cold do continually depend upon the actual presence and influence of the manifest Efficient Causes, as the Light of the Air depends upon the Sun or Fire, or other Luminous Bodies. To this is annexed an Account of the Italian way of making Conservatories of Ice and Snow, as the Author had received it from that Ingenious and Polite Gentleman, Master J. Evelyn.