Page:Philosophical Transactions - Volume 001.djvu/184

 off; Our Noble Author insists most upon giving us his thoughts of the former, videl, the Æquilibrium of Liquors: Which Discourse consisting partly of Conclusions, and partly of Experiments, the former seem to Him, to be almost all of them consonant to the Principles and Laws of the Hydrostaticks; but as for the latter, the Experimental proofs, offered by M. Paschall for his Opinions, are by our Author esteemed such, that he confesses, he hath no mind to make use of them: for which he alledges more reasons than one; which, doubtless, will appear very satisfactory to Intelligent Readers.

Wherefore, instead of those Paschalian Experiments, there is in this Treatise deliver'd a far more Expeditious way, to make out, not only most of the Conclusions, agreed on by these two Authors, but others also); that M. Paschall mentions not; and that with so much more ease and clearness, that persons, but ordinarily versed in the common principles of Hydrostaticks, may readily apprehend, what is deliver'd, if they will but bring with them a due Attention, and Minds disposed to prefer Reason and Experience to Vulgar opinions and Authors.

It not being our Authors present Task, to deliver a Body of Hydrostaticks, but only some Paradoxes, which he conceives to be proveable by his New way of making them out, he delivers them in as many distinct Propositions; after each of which, he endeavours, in a Proof or an Explication, to show, both that it is true; and why it ought to be so.

The Paradoxes themselves (after a premised Postulatum) are these:

1. That in Water, and other Fluids, the Lower parts are pressed by the Upper.

2. That a lighter Fluid may gravitate or weigh upon a heavier.

3. That, if a Body, contiguous to the Water, be altogether, or in part, lower than the highest level of the said Water, the lower part of the Body will be pressed upward by the Water, that touches it beneath.

4. That in the Ascension of Water in Pumps, &c. there needs nothing to raise the Water, but a Competent weight of an External Fluid.

5. That the pressure of an External Fluid is able to keep an Heterogeneous Liquor suspended at the same height in several Pipes, though these Pipes be of very different Diameters.

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