Auroras.—­Clearly most frequent and intense in years of maximum sun spots; this argues connection with the sun.

Points noticed requiring confirmation: 

Arch:  centre of arch in magnetic meridian.

Shafts:  take direction of dipping needle.

Bands and Curtains with convolutions—­not understood.

Corona:  shafts meeting to form.

Notes required on movement and direction of movement—­colours seen—­supposed red and possibly green rays preceding or accompanying movement.  Auroras are sometimes accompanied by magnetic storms, but not always, and vice versa—­in general significant signs of some connection—­possible common dependents on a third factor.  The phenomenon further connects itself in form with lines of magnetic force about the earth.

(Curious apparent connection between spectrum of aurora and that of a heavy gas, ‘argon.’  May be coincidence.)

Two theories enunciated: 

Arrhenius.—­Bombardments of minute charged particles from the sun gathered into the magnetic field of the earth.

Birkeland.—­Bombardment of free negative electrons gathered into the magnetic field of the earth.

It is experimentally shown that minute drops of water are deflected by light.

It is experimentally shown that ions are given off by dried calcium, which the sun contains.

Professor Stoermer has collected much material showing connection of the phenomenon with lines of magnetic force.

Thursday, May 4.—­From the small height of Wind Vane Hill (64 feet) it was impossible to say if the ice in the Strait had been out after yesterday’s wind.  The sea was frozen, but after twelve hours’ calm it would be in any case.  The dark appearance of the ice is noticeable, but this has been the case of late since the light is poor; little snow has fallen or drifted and the ice flowers are very sparse and scattered.

We had an excellent game of football again to-day—­the exercise is delightful and we get very warm.  Atkinson is by far the best player, but Hooper, P.O.  Evans, and Crean are also quite good.  It has been calm all day again.

Went over the sea ice beyond the Arch berg; the ice half a mile beyond is only 4 inches.  I think this must have been formed since the blow of yesterday, that is, in sixteen hours or less.

Such rapid freezing is a hopeful sign, but the prompt dissipation of the floe under a southerly wind is distinctly the reverse.

I am anxious to get our people back from Hut Point, mainly on account of the two ponies; with so much calm weather there should have been no difficulty for the party in keeping up its supply of blubber; an absence of which is the only circumstance likely to discomfort it.

The new ice over which I walked is extraordinarily slippery and free from efflorescence.  I think this must be a further sign of rapid formation.