300 Proceedings of Royal Society of Edinburgh. [sess. 
congelation by tbe refrigerating liquid which circulates in a coil of 
pipes close to the roof of the chamber. 
The refrigerating chamber is placed in the central laboratory ; the 
cold chamber is immediately below in the hold, where it occupies 
a space of about five cubic metres. A branch pipe takes the 
refrigerating liquid to the laboratory tables, to be used in delicate 
biological experiments. On the other hand, the cold chamber is 
large enough to accommodate a part of the ship’s provisions. 
The water-still is a “ Yaryan ” apparatus, very simple and powerful 
for its size, which furnishes 2J tons of fresh water per twenty-four 
hours for use in the boilers and the laboratories. 
Several steam-engines are to be found at different points in the 
ship ; a winch for working the dredge ropes and lighter lines for 
temperature and other observations is fixed to the deck in front of 
the foremast, and can lift 6 tons to a height of 1 metre in a second. 
A sounding-machine, which I have constructed on new ideas is 
fixed in front of the mizzen-mast ; it acts automatically, and can 
indicate any depth to be found in the sea. 
A large reel with two drums works in' the hold. It carries on 
one side 6000 metres of cable in one length, to which a reserve of 
4000 metres of stronger cable is ready to be joined for very great 
depths. On the other side there are 5000 metres of cable, divided 
into lengths of 500 metres. 
The first will be used for dredging, the second for sending down 
pots, and generally for operations which require the apparatus used 
to remain at the bottom of the sea for a time, while the cable is 
buoyed. Finally, there is another small double reel, which is very 
light, and carries pieces of cable varying from 100 to 500 metres in 
length, which are used for small operations, for which it would be 
useless or inconvenient to use longer pieces. 
To summarise, the actual equipment of the ship allows of sounding 
everywhere, dredging in 8000 metres, and laying out pots or other 
apparatus on the bottom at depths up to 6000 metres without the 
least difficulty. 
The stoke-hold is arranged in a way suitable to the equipment 
of the ship. It contains two boilers, a small and a large one. The 
first is used to drive the auxiliary machines (winch, dynamo, &c.), 
and when applied to the main engines can drive the ship three 
