202: 
gum-dragon tree, in the Botanic Gar- 
den, Trinity College, Dublin, 114. 
Maclaren (C.) on traces of ancient gla- 
ciers in Glenmessan, 90. 
Magnesia, on the optical properties of 
the cyanurets of platinum and, 5; on 
the action of the soap-test upon water 
cortaining a salt of, 49. 
Magnetic charts of declination, on a me- 
thod for computing, 3. 
Magnetic declination, on the effect of 
height in the atmosphere on the diur- 
nal variation of, 7. 
Magnetic force, on the effect of height on 
’ the diurnal variation of the horizontal 
complement of the, 7. 
Magnetic induction in crystalline sub- 
stances, on the theory of, 23. 
Magnetic lines in Yorkshire, isoclinal, 14. 
Magnetism, 3. 
Magnetometer, on the construction of 
silk suspension threads for the declina- 
tion, 10. 
Magneto-optical properties of crystals, 
on the, 23. 
Magnets, on the artificial, made by M. 
Logeman, 4 ; on the mechanical com- 
pensation of the bifilar and balance, 
for variations of the magnetic moment 
with temperature, 9. 
Makerstoun, on the daily formation of 
clouds at, 36. 
Malaga, on the present condition of the 
city and neighbourhood of, 151. 
Mammalia, presentation by Mr. Whin- 
copp of a collection of the bones and 
teeth of, 192. 
Manchester, on some extraordinary elec 
trical appearances observed at, on July 
16, 1850, 31. 
Mantell (Dr. G. A.) on the upper jaw of 
the Iguanodon, 125. 
Martins (Dr. C.) on the six climates of 
France, 46; parallel between the su- 
perficial deposits of the basin of Swit- 
zerland and those of the valley of the 
Po in Piedmont, 90. 
Mathematics, 1. 
Matteucci (Prof.) on the conductibility 
of the earth, 56. 
M‘Coy (Prof.), list of organic remains in 
the frontier chain of Scotland, 107. 
M‘William (Dr. J. O.) on the use of the 
Bofareira as a means adopted by the 
natives of the Cape de Verd islands to 
excite lactation, 132. 
Mean pressureat Greenwich and Makers- 
toun, on the variation with season of 
the differences of the, 7. 
Mechanical science, 169. 
INDEX II. 
Menai Straits, &c., on the geological po- 
sition of the black slates of, 102. 
Menstruation in woman, on the causes 
whichadvanceor retard the appearance 
of the first, 135. 
Meteorology, 31. 
Meteorological observations madeat Kaaf- 
jord, near Alten, in Western Finmark, 
and at Christiania in Norway, 36; on 
hourly, made in Thibet at an elevation 
of 18,400 feet, 43. 
Meteorological phenomena at Huggate 
for 1849, 42. 
Meteorological Society, on the British, 
42. 
Meteors, 23. 
Microscope, on the application of photo- 
graphy to the compound, 126. 
Milk, on the presence of fluorine in, 67. 
Miller (Hugh) on certain extraordinary 
peculiarities of structurein the more an- 
cient ganoids, 91; on peculiarscratched 
pebbles and fossil specimens from the 
boulder clay, and on chalk flints and 
oolitic fossils from the boulder clay in 
Caithness, 93. 
Milward (A.) on the present condition of 
the city and neighbourhood of Malaga, 
and on the preparation of raisins, 
151. 
Minerals, on the condensation of volume 
in highly hydrated, 60. 
Mirage, on some phenomena of, on the 
east coast of Forfarshire, 42. y 
Mollusca, on the dentition of the Britis 
pulmoniferous, 126. 
Monstrosities, on the laws regulating the 
development of, 138. 
Moon’s first quarter during 1839-50, re- 
markable thermometrical maxima at or 
near the, 32. 
Morphology of the muscular system, 138. 
Motion, on a physiological mode of re- 
solving the metaphysical difficulties as 
‘to the origin of the notion of, 135. 
Mulder (Prof. G. I.) on the presence of 
carbonates in blood, 57. ᾿ 
Mull, island of, on a fossiliferous deposit 
underlying basalt in the, 70; on the 
recent discovery of plumbago or gra- 
phite in the island of, 102. 
Murchison (Sir Roderick Impey) on the 
discovery of palzozoic fossils in the 
crystalline chain of the Forez in France, 
and on lines of dislocation between the 
lower and upper carboniferous deposits 
of France and Germany, 96; review 
of the labours of M. Barrande in pre- 
paring his work “ The Silurian System 
of Bohemia,” 97. : 
ΜΝ μεν... lh 
