The CONTENTS.

C H A P. V.

stfabanitb,

I« General Laws of Motion ; by

X Dr. Wallis p. 545

2- By Sir Chr. Wren 547

3. By M. Hugens <548

4- Some Historical Passäges rehting 10 thesePapers; ly Mr. Oldenburgh 549

II. The Synchronism of tbe Vibration; tnade in

a Cycloide ; Demovftratei by « Person ojQuality 550

III. 1. A Problem concerning tbe Line oftkeQuiekest Descent betroeen ttvo Pointtgi-ven ; Proposed by M- Jo. Bernouilli 5 51

2. Solv’d by . . . ibid.

3. Jhe Demonstration ; by Mr. R. Sault ibid.

IV. Horn mucb tbe Descent U Quicker in theCycloide, thun in a Straigbt Line; by

- - - 55Z

V. i- Extä Portable Watches; by ctl. Hu-gens ibid.

2. By Dr. Goth. Guil. Leibnitz 5 54

VI. A Clocb Ascendant upon an Indined

Plain; by M. deGennes 555

VII. A Clodt Descendent 0» 4 Plain Indined ;

by Mr. Maurice Wheeler 5 5 6

VIII- Tbe Effeäsof Gravity in tbe Descent ofHeavy Bodies, and tbe Motion of Pro-jetts ; by Mr. Halley 560

IX. TbeMeasure of tbe Airs Resistancen!Bo-dies, movedinit-, by Dr. Walüs 572

X. 1. Experiments to Determine tbe Point-

Blank Diftance, the Charge of Powder^ andtbe best Si^e of Guns; proposed by Sir Ro-bert Moray 580

4. Experiments for tryivg tbe Force e/GreatGuns; by Mr. Greaves 583

XI. Shooting ä/ tie Rarefaction of tbe Air; by

Dr. Papin 584

XII. Jbe Velocity roher cmtb tbe Air Jfußei in-

to an Exhausted Receiver; by Dr. Pa-pin 58;

XIII. Wind produced by the Fall of Watet ;

by Dr. Walt. Pope 586

XIV. Tbe best Perm es Horizontal Sails for «

Mill; by Dr. Rob. Hook ibid.

XV. 1. An Account of Flying; by Dr. Rob.

Hook 587

2. 7l>e Art of Flying; by S- Besnier 588

z. A Flying Chariot ; by Fr. Lana ibid.

S he ton Impracticable 1 by Dr. Hook 589

XVI- An Engine to mähe Linnen Clotb . byM- de Gennes ibid.

XVII. Advantages of High Wheels Experi-mtnted ; by a Member of tbe Oxford So-ciety 591

XVIII. A New Sort of Calesh; deferibed bySir R. B. 552

XIX. Tbe Contrirance of t Perpetual Moti-on ; by . . . ExpUbted ; by Dr. Papin

ibid.

And Jbe ton Jnfufficient by bim 593

XX. The Speaking Trumpet Improv'i -, by

J. Ccnyers ibid•

XXI. TheSwiftness of Sounds, and tbeir Rc«stections.ar Ecchoes ; by Mr. Walker 594

XXII. , Tbe Doctrine oj' Sounds; by Narcissus,

Bijbop es Ferns end Leighlin 596

XXIII. A Paper of lest General Vfe, omitted

6 02

XXIV. Accounts of Books, and Addit ions,Omitted ibid.

C H A

Hjdrostetticks.

I. 1 . 'T"*0 Weigh Water, and otber Fluids;

X by • • • p. 603

2. A New Aräometer; by JW.Homberg ibid .

II. 1 . A New Essay Instrument ; by Mr.

Boyle 604

2. Furtber Confidcr’d 3 by . . . 608

P. VI.

Hydraitlickt.

III. The IFeight of Water in Water; by Mr.

Boyle ibid.

IV. x. The Pressure of Mieter in Great Depths >

by a Person of Honour 609

2. By Dr. Oliver ibid.

V. 1. Tbt