406 Proceedings of Royal Society of Edinburgh. [sess. 
ice, but this would not obstruct the steamer following. With 
regard to this, a large ice-breaker is preferable to a small one, as 
the large ice-breaker leaves a larger channel and destroys the ice 
more efficiently on its passage. 
Holding the above-mentioned views, I opened my ice-breaking 
campaign by addressing the Geographical Society of St Petersburg 
in the month of March 1887. I proposed to build an ice-breaker of 
10,000 horse-power with four engines of equal size, three of them 
being placed at the stern and the fourth at the bow of the ship. 
The lecture interested many people in the subject. Professor 
Mendeleeff, who is well known in England, was first to join me. The 
Minister of Finance of my country, Mr Witte, took a great interest 
in my proposition, and said to me that if my ideas were correct, and 
if really the ice-breakers could deal with Pinnish Gulf and Kara Sea 
ice, then they would be of great service to the commerce of Russia. 
On his suggestion I made a voyage to the Kara Sea, and on my return 
the question was studied by the Commission, and it was on the repre- 
sentation of the Minister of Finance that His Majesty the Emperor 
of Kussia authorised one experimental ice-breaker to be con- 
structed. 
Several shipbuilding firms were invited to tender, and that of 
Messrs Sir W. G. Armstrong, Whitworth & Company, Limited, 
which promised better conditions, was accepted. It is a strik- 
ing fact that the first steam tug that Britneff turned into an 
ice-breaker was built at the same yard some forty years ago. 
Lately, the same firm was engaged in building several ice-breakers 
for the River Volga, the Port of Hango, and the Lake of Baikal, 
and I may state that they have done their best to fulfil the very 
extraordinary conditions that I have put upon them, which were 
necessary in building a polar ice-breaker. 
I will not take up much of your time in the technical details of 
the ship ; the model here exposed (Plate XII.) shows the exterior. 
You will notice that the submerged part has no vertical lines, even 
in the midship section there is an angle of 20° from the vertical 
line, and her bow and stern lines are inclined 70° and 65° respec- 
tively from the vertical line. 
The ship has a double bottom and wing passages throughout the 
whole length. Transversely, the ship is divided by eight principal 
