228 H. C. RUSSELL. 
mometers were taken every five minutes, (that is every mile as 
we approached and as we receded from the berg); beyond a fluc- 
tuation of perhaps half a degree, no definite variation of tempera- 
ture occurred. A mean of the angular observations gave three 
hundred feet high by seven hundred feet by one thousand and 
fifty feet as the dimensions of this berg. 
In this particular part of the ocean the icebergs almost invari- 
ably have table tops which are corrugated and generally yellow, 
the colour being due to numberless birds probably resting on them 
at night. The top of this one being a long way above the line of 
spray even in a very heavy gale. Notwithstanding the long heavy 
swell it showed no signs of rolling or rising to the sea. The debris 
of broken pieces formed a line almost directly to the leeward of the 
berg, in fact every berg we saw had the debris drifting almost 
directly to the leeward of the berg. It would therefore, appear 
to be safer for a sailing ship or steamer, if possible, to go to the 
windward of an iceberg and get clear of the large pieces which 
are in many cases large enough to injure a vessel in case of collis- 
ion. Large flocks of the blue petrel or whale bird seem to enjoy 
flitting about amongst the broken water around ; these ‘birds 
require large quantities of food, but their food must consist of 
animalcules which abound on the surface of the sea, as they seldom 
take to swimming on the water. It cannot be the scraps that go 
overboard from a ship that feed the hundreds of large birds now 
following in the wake of the ship. They seem to keep on the 
wing all day without being seen to pick up food of any kind. 
I particularly wished to know if a ship could pass close to an 
iceberg with safety, as I have read so often about ships striking 
against the perpendicular sides, and large masses of ice falling on 
their decks. In every berg witha flat table top there is apparently 
deep water up to the perpendicular sides. The breaking sea 
apparently wears this perpendicular part away quickly. If in 
any part the water is shallow it is clearly discernible, being of a 
milky blue appearance. A sharp loud detonation was heard on 
passing this berg, but no particular attention was given to it as I 
