TRANSIT OF MERCURY. 169 
10h. 40m., S.M.T., thin clouds passing ; tried the full aperture 
again with two coloured glasses ; exchanged for the darkest glass 
and 2-inch aperture, which is best. Large solar halo, 12h. 13m., 
$.M.T., took off the 2-inch stop ; clouds getting thicker ; the sun’s 
limb well defined. At 12h. 25m., 8.M.T., the white spot very 
persistent. lh. 35m., S.M.T., hazy and light clouds passing. 
lh. 40m. 10-40s., S.M.T, internal contact at egress, both limbs 
moderately well defined; cusps sharp. lh. 42m. 0.09s., 8.M.T., 
last contact. 
LAW. HARGRAVE, 
Extra Observer (Astronomical). 
Report from F. M. Bladen. Place, Katoomba. 
Weather. 
The weather in early morning was very clear and warm, Strips 
of cirro-stratus cloud flying on horizon east and west. 
Instrument. 
The instrument was a refractor by T. Cooke, of York, England. 
mounted equatorially, with clock motion. Fo ength, 5 feet ; 
aperture, 4} inches (stopped down to 2 inches) ; eye-piece solar, 
diagonal, power about 80, light blue tinted glass shade. 
: Ingress. 
Definition very good indeed ; sun’s limb being very clear and 
sharp, and sun spots and facule very distinct. 
First contact. 
First external contact took place at 8 hours 22 minutes 3:34 
Seconds, Sydney mean time, when slight indent was visible, which 
in a second or two had become too marked to be mistaken. 
Definition of cusps. 
The outline of the planet as it crept on the sun was very clear 
and well defined—cusps sharp and distinct. 
Haze. 
This continued until the planet was about ? of its diameter on 
the sun, when a light cirrus cloud passed over, rendering the cusps 
very indistinct and tremulous. 
Estimated first internal contact. 
At 8 hours 23 minutes 24:64 seconds, Sydney mean time, I 
thought from the irregular shape of Mercury that internal con- 
tact would be complete, and that it would be visible but for bad 
definition and unsteaciness. 
=a First internal contact. 
Tt was not, however, until 8 hours 23 minutes 42°84 seconds, 
Sydney mean time, that a band of light was visible between 
