1864. | The Royal Society. 299 
THE ROYAL SOCIETY. 
Tux papers read before the Royal Society during the past quarter have 
been of their usual varied character. They embrace the whole circle 
of the sciences, but the communications to which we shall chiefly allude 
in these pages are those relating to natural and physical science. 
Among these we find one of a very abstract nature, “On the Condition, 
Extent, and Realization of a Perfectly Musical Scale on Instruments 
with Fixed Tones,” by Mr. Ellis. It was a very recondite paper, which 
could only be made intelligible to those profoundly acquainted with 
the science of music and by the help of extended diagrams. 
Chemists have taken but a small share in the proceedings of the 
Royal Society this quarter. Dr. Stenhouse contributed a short paper 
on Rubia munjista or the Madder of the East Indies, in continuation of 
& paper communicated to the Society last year. Among the new facts 
contained in this paper was the analysis of the colouring principle of 
Kast India madder, to which Dr. Stenhouse has given the name of Mun- 
jistine. He found it to be closely allied in composition to the colouring 
- matters obtained from Turkey, and Continental madders. Munjistine, 
though existing in larger quantity in Munjeet, than Alizarine in 
the best Naples madder, has unfortunately much less tinctorial power, 
and consequently the value of East India madder as a dye stuff is much 
smaller than that of either Turkey or Naples. From the purpurine of 
munjeet Dr. Stenhouse has produced a new dye, by dissolving it in 
ammonia, and allowing the solution to rest in a warm place for about 
a month, occasionally replacing the ammonia and water lost by evapo- 
ration. The purpurine disappears, and a new colouring matter is formed 
which dyes unmordanted silk and wool of a fine rose colour, but will 
not dye even mordanted vegetable fibre. The author gives the name 
purpureine to this new dye. 
A paper of great scientific interest on the Acids of the Lactic series 
was communicated by Messrs. Frankland and Duppa. 
Terrestrial magnetism now attracts a large share of attention, and 
the results of the observations made will some day lead to important 
consequences. At present we must reckon among the curiosities of 
science, the mysterious connection which seems to exist between the 
magnetism of our earth and the spots on the sun. Dr. Wolf, of 
Zurich, has gone over a table of the magnetic variations observed at 
Greenwich for several years, and compared it with his own observations 
of sun-spots, finding the years which show the greatest magnetic devia- 
tions to have been richest in sun spots. 
The beautiful self-recording magnetographs at Kew have been 
adopted in the Observatory at Lisbon, and Senhor Capello, of the 
Lisbon, and Mr. Stewart of the Kew, Observatories, now send to the 
Royal Society the results of a comparison of certain traces produced 
simultaneously at the two places, during the magnetic disturbances in 
July last year. It seems that when the Kew and Lisbon curves are 
compared together, a very striking similarity is found to exist between 
the horizontal force, one perhaps less striking between the declination 
