424 
Progress in Science . 
[July, 
ducing chemical changes, and that too little account has hitherto been taken 
of the nature of the substance in which the decomposition is produced, 
io. Finally, Dr. Draper has recently published researches on the distribution 
of heat in the spedirum, which are of the highest interest, and which have 
largely contributed to the advancement of our knowledge of the subjedt of 
radiant energy. Through ill-health, Dr. Draper was unable to receive the 
medal in person. He therefore sent the following letter, which was read by 
Mr. Quiney : — 
“ To the American Academy of Arts and Sciences. — Your favourable 
appreciation ot my researches on radiations, expressed to-day by the award of 
the Rumford Medal — the highest testimonial of approbation that American 
science has to bestow on those who have devoted themselves to the enlarge- 
ment of knowledge — is to me a most acceptable return for the attention I have 
given to that subjedt through a period of more than forty years, and I deeply 
regret that through ill-health I am unable to receive it in person. Sir David 
Brewster, to whom science is under so many obligations for the discoveries he 
made, once said to me that the solar-spedtrum is a world in itself, and that 
the study of it will never be completed. His remark is perfedtly just. But 
the spedtrum is only a single manifestation of that infinite ether which makes 
known to us the presence of the universe, and in which whatever exists — if I 
may be permitted to say so — lives and moves and has its being. What objedt, 
then, can be offered to us more worthy of contemplation than the attributes 
of this intermedium between ourselves and the outer world ? Its existence, 
the modes of motion through it, its transverse vibrations, their creation of the 
ideas of light and colours in the mind, the interferences of its waves, polarisa- 
tion, the conception of radiations and their physical and chemical effedts — 
these have occupied the thoughts of men of the highest order. The observa- 
tional powers of science have been greatly extended through the consequent 
invention of those grand instruments, the telescope, the microscope, the 
spedtrometer. Through these we have obtained more majestic views of the 
nature of the universe. Through these we are able to contemplate the struc- 
ture and genesis of other systems of worlds, and are gathering information as 
to the chemical constitution and history of the stars. In this noble advance- 
ment of science you, through some of your members, have taken no incon- 
spicuous part. It adds impressively to the honour you have this day conferred 
on me, that your adtion is the deliberate determination of competent, severe, 
impartial judges. I cannot adequately express my feelings of gratitude in 
such a presence publicly pronouncing its approval on what I have done. — I 
am, gentlemen, very truly yours, John W4Draper.” 
Microscopy. — In a memoir devoted to the subjedt of amyloid degeneration 
of the kidney, liver, and spleen, which appears in a recent part of the 
“ Archives de Physiologie,” M. Corml gives the results of his experiments 
with several new colouring matters. Two of these were methyl-aniline violets 
discovered by M. Lauth ; the third was a violet discovered by Dr. Hofmann, 
of Berlin. The preparations can be stained with these violets either when 
fresh or after being hardened in spirit ; and the colouring agents have this 
peculiarity, that certain tissues, as cartilage, decomposes them into a 
violet-red and a blue-violet, each of which becomes fixed in different elements 
of the tissue ; the hyaline matrix, for example, assuming a red colour, whilst 
the nuclei and cellules, as well as the cartilaginous capsules, become of 
a blue-violet tint. The normal tissues of the liver, kidney, and spleen, how- 
ever, do not decompose the violets, but, when amyloid degeneration is present, 
the degenerated and semi-transparent parts resembling colloid become of a 
violet-red, whilst the normal elements are tinted of a violet-blue, and thus a 
means equal, if not superior, to that of iodine is afforded, by which the 
changes may be followed. 
The researches of the Rev. W. H. Dallinger and Dr. Drysdale, on monads 
with high powers, have led to some improvements in the mode of illumination 
employed in such observations. Great stress is laid upon the necessity of 
accurate centreing throughout every part of the microscope. The contrivance 
