1898 - 99 .] Admiral Makar off on Oceanographic Problems. 397 
the denser water sinks down, the lighter water tries to rise on the 
top of it. The difference of level which is produced hereby brings 
to the surface the cold water of the lower strata (for particulars 
see paragraph 261 of my book Le Vitiaz et V Ocean pacijique). 
I studied this Strait in 1887 and 1888, and published the results 
of my study, but when I came to the Pacific again in 1895, as the 
admiral commanding the squadron, I was very anxious to go to 
the Strait of La Perouse to re-investigate the currents, and now 
I am in possession of very valuable material on this subject, which 
is almost ready for publication. 
I do not propose to take up more of your time at present with 
particulars of these five straits. Those who desire further informa- 
tion may refer to my book Le Vitiaz et V Ocean pacijique, published 
in the Russian and French languages, and also my book on the 
A 
Exchange of Waters between the Black Sea and Mediterranean. 
I only wish to remind you what important information the ther- 
mometer and hydrometer can give in the study of the different 
parts of our so little-known planet. You know better than I, that 
studies in that direction ought to be continued, and no nation in 
the world has been so liberal as England, which found means to 
send out for four years the “ Challenger,” with a scientific staff to 
explore the deep sea. But it is not always possible to find such 
means, and it is advantageous to associate ordinary seamen with 
that kind bf work. Scientific societies might contribute very much 
in discussing the data collected by the ordinary seamen, and I wish 
now to refer to the manner of collecting data regarding the tem- 
perature of the superficial water. 
Up to the present time it has been the custom to publish only 
charts of the temperature ; I find that this system is not quite 
efficient ; charts of temperature are very useful, but when the 
number of observations increases and one wishes to publish a new 
chart one does not know what value to attach to the previous 
chart, and has to do the same work over again. 
In my book Le Vitiaz et V Ocean pacifique I have made a 
particular study in this respect of the Northern Pacific Ocean, and 
I collected from the log books of Russian vessels all the informa- 
tion that I could find. I divided the sea into 1° squares and gave 
to each ship one little column ; the following table is an example 
of the method adopted : — 
