XX CONTENTS. 
TETRAMETHYLPIPERIDINE (On zz'-). 270. 
THERMODYNAMIC POTENTIAL (Osmotic pressure and). 741. 
THERMOMETER (Comparison of the platinum thermometer with the hydrogen). 290. 
THREE-PIIASE LINES (Critical terminating points in) with solid phases in binary systems 
which present two liquid layers. 556. 
TOLUIDINE (On the preparation of pure o-) and a method for ascertaining its purity. 395, 
TONES of different pitch (On the relative sensitiveness of the human ear for), measured 
by means of organ pipes. 549. 
TRIANGLES (Approximate formulae of a high degree of accuracy for the) in the deter- 
mination of an elliptic orbit from three observations. 752. 
TRIANGULATION (The connection between the primary) of South-Sumatra and that of 
the West-Coast of Sumatra. 453. 
TRINITROVERATROL (On). 462. 
TRITHIOACET (The intramolecular transformation in the stereoisomeric g-and @-) and 
g-and -thrithiobenzaldehydes. 329. 
TRUNK-MYOTOME (On the form of the). 34. 
— (Note on the innervation of the). 708. 
TUBERCULARIACEA (On Hymenopsis ‘Typhae (Fuck.) Sace.. a hitherto insufficiently 
described), occurring on the withered leafsheaths of Typha latifolia. 206. 
TYMSTRA BZ. (s.). On W. Marckwatp’s asymmetrie synthesis of optically active 
valeric acid. 465. 
— and C. A. Losry pe Bruyn. The mechanism of the salicylacid synthese. 63. 
umMBILIcs (Multiple) as singularities of the first order of exception on point-general 
surfaces. 386. 
URINE of fishes (On the osmotic pressure of the blood and). 537. 
VALERIC Aci (On W. Marckwatp’s asymmetric synthesis of optically active). 465. 
vapors (Application of the Baroscope to the determination of the densities of gases 
and). 770. 
vapour (The determination of the conditions of coexistence of) and liquid phases of 
mixtures of gases at low temperatures. 233. 
— (A formula for the osmotic pressure in concentrated solutions whose) follows 
the gas laws. 723. 
VARIABILITY of some plants (On the influence of nutrition on the fluctuating). 398. 
VERSCHAFFELT (J, E.). The influence of admixtures on the critical phenomena 
of simple substances and the explanation of TErcHNER’s experiments. 474, 
VERSLUYS (w. A.). The relation between the radius of curvature of a twisted curve 
in a point P of the curve and the radius of curvature in P of the section of 
its developable with its osculating plane in point P. 277. 
viscosity (The) of the system hydrazine and water. 329. 
VISSER (a. w.). A few observations on autocatalysis and the transformation of 
y-hydroxy-acids, with and without addition of other acids, conceived as an 
ion-reaction. 760. 
VRIES (e. DE). Note on the Ganglion vomeronasale. 704. 
