96 Descriptive Characters of 
light charcoal points in a galvanic battery, and the light 
of the sun. 
Now, although we do not know by what property of the 
eye rays less refrangible than the extreme red become invisi- 
ble, yet this will appear on inspection to be a wise arrange- 
ment of Providence. 
For if the rays which emanate from bodies at ordinary 
temperatures were invisible they would overpower those 
exquisitely beautiful colours of nature which are produced by 
reflection of the solar light; besides which, there would be 
no such thing as darkness, even when the eye was closed, for 
light would still issue from the eyelids. And again, if rays 
did not become visible till at a much higher temperature than 
600°, combustion would go on in darkness, and we should 
never be warned of the presence of fire. 
Finally, if we suppose a number of bodies (for simplicity’s 
sake spheres) to have been originally at the same temperature, 
it is clear, that since radiation will vary with the surface 
exposed, large spheres, the surface of which bears a less 
proportion to their solid contents than that of smaller ones, 
will cool more slowly than smaller ones; so that at any given 
time a large sphere would be at a much higher temperature 
than a small one, and would, consequently, emanate visible 
rays, while the rays of the other would be invisible. 
Therefore, in a system of bodies, such as the solar system, 
the centre of attraction is also the centre of illumination 
which is a most wise and beneficial arrangement. 
Art. XJ.—Descriptive Characters of New Alpine Plants, 
from Continental Australia. By Dr. FERDINAND MUELLER. 
In offering this small, yet perhaps not unwelcome contribution 
towards the botany of Australia, I wished to conclude the 
precursory diagnostic notes on our Alpine flora, of which 
some scattered fragments appeared in this journal, and in the 
papers of the Victorian Institute.* ; 
* The plants there enumerated and described are the following :—Hriostemon 
lancifolius, P. phylicifolium, Phebalium ozothamnoides, Ph. podocarpoides, Crowea 
exalata, Scleranthus miaroides, Kunzea ericifolia, Burtona subalpina, Oxylobium ~ 
alpestre, Bossiza distichoclada, Kurybia megalophylla, Eurybia alpicolo, Brachy- 
come, multicaulis, Br. nivalis, Antennaria nubigena, Gnaphalium alpigenum, 
Agrostis nivalis, Agr. frigida, Agr. gelida, Danthonia robusta, Hierochloe 
submutica, and Astelia psychrocharis. A few as doubtful remained yet 
uncharacterized. 
