132 Miscellaneous Intelligence. 



this flood on our knees, for the scene was sublime in itself, while the 

 subject — an abundance of water sent to us in the desert — greatly 

 heightened the effect to our eyes. Suffice it to say, I had witnessed 

 nothing of such interest in all my Australian travels. Even the heav- 

 ens presented something new, at least uncommon, and therefore in har- 

 mony with this scene ; the variable star r\ Argus had increased to the 

 first magnitude, just above the beautiful constellation of the southern 

 cross, which slightly inclined over the river, in the only portion of sky 

 seen through the trees. That very red star, thus rapidly increasing in 

 magnitude, might, as characteristic of her rivers, be recognized as the 

 star of Australia, when Europeans cross the line. The river gradual- 

 ly filled up the channel nearly bank high, while the living cataract 

 travelled onward, much slower than I had expected to see it ; so slowly, 

 indeed, that more than an hour after its first arrival the sweet music of 

 the head of the flood was distinctly audible from my tent, as the mur- 

 mur of waters and the diapason crash of logs travelled slowly through 

 the tortuous windings of the river bed. I was finally lulled to sleep by 

 that melody of living waters, so grateful to my ear, and evidently so 

 unwonted in the 1 dry bed of the thirsty Macquarie. Thermometer at 

 sunrise, 47°; at noon, 79°; at 4 p. m., 88°; at 9, 63°— with wet bulb, 57°. 



8. On the Apparent Motion of the Figures in certain Patterns of 

 Blue and Red Worsted ; by Henry Taylor, Esq., (Phil. Mag., xxxiii, 

 345, Nov., 1848.) — The apparent motion of the figures in certain pat- 

 terns of blue and red worsted is sufficiently well known to have excited 

 some attention among the learned as well as the unlearned, but, so far 

 as I know, without receiving any satisfactory explanation. After hav- 

 ing examined the subject for some time, I believe I have succeeded in 

 making out the cause of this singular phenomenon ; and if the follow- 

 ing observations are deemed of sufficient importance, I should be glad 

 to have them inserted in the pages of your Journal. 



If certain patterns of blue and red worsted-work are examined by 

 candle-light, it is found that when they are moved about, the figures 

 have a tremulous appearance as if they were moving faster than the 

 ground of the pattern — and biue and red are the only colors exhibiting . 

 this remarkable property — although it must be observed that some per- 

 sons are so constituted as not to perceive the illusion under any circum- 

 stances. 



The usual patterns consist of blue and red figures on a ground of 

 the opposite color, several of them being arranged together on the 

 same piece ; but for the purpose of experiment, it is better to have 

 patterns of the simplest kind, and I shall suppose them now to consist 

 of single spots, of red on a blue ground and blue on a red ground. 



If the pattern is moved up and down before the eye, and attention is 

 directed to the red spot, we may observe a change of color taking 

 place at its edge, like a dark border or shadow flitting from one side to 

 the other. On close examination, it will be found that as the pattern is« 

 moved upward, this dark border appears only at the upper edge of the 

 6pot, and but for an instant ; as the pattern descends, it is seen again 

 at the lower edge, vasishing as before. When the movement is made 

 from side to side, instead of up and down, a similar appearance may 

 be seen on the right and left of the spot. 





