128 RAMBLES OF A NATURALIST. 



presides over the fitting up of our ships, in which 

 the space seems doubled by the judicious use which 

 is made of the smallest corner of available room. 



Let us now return to the spiral staircase which 

 has brought us thus far, and which will carry us at 

 once to the portion of the edifice which is more 

 particularly destined to fulfil the special purpose for 

 which the tower is designed. The eighth story 

 contains vessels of oil, glasses, revolving lamps, some 

 admirable instruments intended for meteorological 

 observations, a thermometer, barometer, and chrono- 

 meter. Here the spiral staircase terminates in a 

 flattened arch which supports a slender pillar, cut 

 into steps, which are the only means of communica- 

 tion with the watch-tower above, in which the men 

 take it by turns to keep guard every night. You 

 will be surprised on looking round to perceive that 

 the apartment is coated with differently coloured 

 marbles, which line the walls and vaulted roof and 

 even cover the floor. But this luxury, which may 

 appear to you to be so much out of place, has been 

 introduced from necessity. The apparatus for light- 

 ing the building enters the room through a circular 

 aperture in the ceiling, and hence the most extreme 

 cleanliness became necessary, which could alone be 

 obtained by the aid of perfectly polished surfaces. 



Let us now ascend the tenth and last flight of 

 steps. Here we are beneath the cupola, and look 

 upon one of those magnificent gifts by which science 

 from time to time enriches mankind, as if to refute 

 the discouraging question that is often asked, Cui 

 bono ? You see before you the machinery by which 



