ty. 
INDEX. 
Pennsylvania, some examples of pressure- 
fluxion in, by Prof. H. C. Lewis, 1029. 
Periodic law, the, as illustrated by certain 
physical properties of organic com- 
pounds, by Prof. T. Carnelly, 969. 
——,, suggestions as to the cause of the, 
and the nature of the chemical ele- 
ments, by Prof, T. Carnelly, 969. 
Perry (Prof. J.) on standards for use in 
electrical measurements, 31. 
Perry (Prof. 8. J.) on comparing and 
reducing magnetic observations, 65, 
89. 
Peter (Rev. J.), the stone circles in Aber- 
deenshire, with special reference to 
those in the more Lowland parts of the 
county, their extent and arrangement, 
singly or in groups, with general obser- 
vations, 1221. 
Petrie (W. M. F.), the discovery of Nau- 
kratis, 1216. 
Phillips (J. G.), the Elgin sandstones, 
1023. 
Philology, African, the progress of, R. N. 
Cust on, 1105. 
*Photo-electricity, further experiments in, 
by Prof. Minchin, 940. 
Photometer, a, made with translucent 
prisms, J. Joly on, 917. 
Photometry with the pentane standard, 
by A. Vernon Harcourt, 916. 
Phyllopoda, the fossil, of the palzozoic 
rocks, third report on, 326. 
Physical constants of solution, report on 
the investigation of certain, especi- 
ally the expansion of saline solutions, 
261. 
*Physical molecular equivalents, Prof. 
Guthrie on, 985. 
Physical Section, the Mathematical and, 
Address by Prof. G. Chrystal to, 889. 
Physiography of Southern India, notes on 
the, by Col. B. R. Branfill, 1124. 
*Physiological experiment, a new kind 
of colour apparatus for, J. Aiken on, 
1079. 
Pickering (S. U.) on the evidence dedu- 
cible from the study of salts, 989. 
Picts, the, and pre-Celtic Britain, by 
Hyde Clarke, 1223. 
Pirie (Prof. G.) on calculating the surface 
tension of liquids by means of cylin- 
drical drops or bubbles, 898; on the 
surface tension of water which contains 
a gas dissolved in it, id. 
*Pitt-Rivers (Gen.) on the working of the 
Ancient Monuments Act of 1882, 1214 
Plant (J.) on the erratic blocks of Eng- 
land, Wales, and Ireland, 322; on the 
circulation of underground waters, 380. 
Plant-digestion, especially as occurring in 
Carica papaya, Dr. 8. Martin on, 1078. 
“Plants, the essential elements of, T. 
Jamieson on, 969. 
1885. 
1249 
Playfair (Sir L.) on the aid given by the 
Dominion Government and the Govern- 
ment of the United States to the en- 
couragement of fisheries, and to the 
investigation of the various forms of 
marine life on the coasts and rivers of 
North America, 479. 
Playfair (Lt.-Col. R. L.) on the re-dis- 
covery of lost Numidian marbles in 
Algeria and Tunis, 1018; on the 
changes which have taken place in 
Tunis since the French protectorate, 
1105. 
Pneumatic system as applied to tele- 
graph purposes, the development of 
the, J. W. Willmot on, 1198. 
*Polarised gas, thermal effusion and the 
limiting pressure in, G. J. Stoney on, 
904. 
Polariser, a new, devised by Mr. Ahrens, 
Prof. 8. P. Thompson on, 912. 
*Polygordius, systématique du genre, by 
J. Fraipont, 1098. 
Polymerisation, the spontaneous, of 
volatile hydrocarbons at the ordinary 
atmospheric temperature, Prof. Sir H. 
E. Roscoe on, 967. 
Polyzoa, eocene, note on the scarcity of, 
by A. Bell, 672. 
——, fossil tertiary, of the higher zones, 
A. Bell on, 666. 
—-—, marine, classification of, 489; geo- 
graphical and bathymetrical distribu- 
tion of, 612. 
, recent, 
graphy, 674. 
, tertiary, from Reggio (Calabria), 
Prof. G. Seguenza’s list of, note on by 
Rev. T. Hincks, 673. 
Porpoise, the chemical composition of 
the milk of the, Prof. Purdie on, 1072. 
*Portuguese possessions in West Africa, 
the, by H. H. Johnston, 1132. 
Potential, a method of multiplying, from 
a hundred to several thousand volts, 
Prof. Sir W. Thomson on, 907. 
Preece (W. H.) on standards for use in 
electrical measurements, 31; on stan- 
dards of white light, 61; onthestrength 
of telegraph poles, 853; on the relative 
merits of iron and copper wire for 
telegraph lines, 907; on domestic 
electric lighting, 1197 
Pressure-fluxion, some examples of, in 
Pennsylvania, by Prof. H. C. Lewis, 
1029. 
Prestwich (Prof.) on underground tem- 
perature, 93; on the erratic blocks of 
England, Wales, and Ireland, 322; on 
the circulation of underground waters, 
380; on the rate of erosion of the sea- 
coasts of England and Wales, 404. _ 
Price-level, the variations of, since 1850, 
M. G. Mulhall on, 1157, 
4. 
biblio- 
report on, 481; 
