June 1, 1883. 1 



SCIENCE. 



481 



color, and the thousand other creatures of vari- 

 ous size, up to the large octopus and the great 

 edible turtle. The aquarium was intended to 

 produce a revenue which should cover a con- 

 siderable proportion of the expenses of the 

 station, — an expectation which has not been 

 fulfilled. Nevertheless, it is appreciated bj^ all 

 who visit it as a source of great delight and 

 interesting knowledge, while it is indispensable 

 to those who work in the station as a means 

 of studj- and a reservoir of material. 



Beneath the floor of the aquarium is a laby- 

 rinth of underground rooms, containing the 

 engines, cisterns, and pumps by which the 

 circulation of water is maintained throughout 

 the tanks and the smaller aquaria in the labo- 

 ratories above. 



To the right of the main entrance to' the 

 public aquarium is a marble staircase, which 

 the uninitiated are forbidden, in various lan- 

 guages, to ascend. It leads up to the part of 

 the building devoted to scientific studies ; and 

 thus immunity is secured from all noise or dis- 

 turbance. The naturalists at work hear only 

 the breaking of the waves, or, at times, the 

 sounds of music from the gardens, and the 

 distant murmur of the city. On the northern 

 side of this second stor}' is the great laboratorjr, 

 lighted by a row of windows twenty-five feet 

 in height. It is fitted up for twelve workers ; 

 the tables, drawers, and shelves of each being 

 so arranged as to form under a window a kind 

 of alcove, which is thus well lighted from the 

 north, and is fitted up independent!}'' with 

 reagents and apparatus. Down the centre of 

 the room is a long aquarium, consisting of two 

 reservoirs, one above the other ; so that, by 

 means of siphons, circulation of sea-water 

 may be kept up in the various vessels which 

 the occupants of the tables use to isolate the 

 animals they are studjing, or to contain ova 

 and embryos in course of development. 



Besides this general laboratorj-, there are 

 twenty small rooms fitted up for the same 

 purpose, each provided with its own apparatus 

 and aquaria. 



The south side of the large laboratory has 

 two windows opening on a central court lighted 

 by a skj-light in the roof, and extending down 

 to» the floor of the public aquarium, whose 

 central tanks are arranged around it. A short 

 bridge across this court leads to the librar}', 

 which corresponds in size to the laboratorj-, 

 and opens on to a spacious loggia ninning 

 along the whole south side of the building. 

 The library' is well furnished and excellently 

 lighted ; and there is scarcelj' a work on any 

 branch of biologj-, classical or recent, or 



SiXij current scientific periodical of reputation, 

 which is not to be found on its shelves. The 

 height and fine proportions of the room are in 

 keeping with the dignitj' of its function ; and 

 its walls are tastefully decorated with interest- 

 ing frescos appropriate to the situation and 

 character of the station. 



To the west of the laboratory and library 

 are the rooms where the material brought into 

 the station is deposited, sorted, and distrib- 

 uted, and where the conservator, Salvatore Le 

 Bianco, and his assistants, preserve specimens 

 for the collection of the station, and for send- 

 ing to distant laboratories or private investi- 

 gators. In one of these rooms are the shallow 

 tubs where the contents of the dredges are 

 poured out, washed, and searched by a number 

 of boys ; and the variet}' of beautiful and in- 

 teresting creatures to be seen here, everywhere 

 around, produces an enthusiastic delight in the 

 zoologist on his first visit ; and the impression 

 is in no waj' lessened when he examines the 

 exquisite collection of preserved specimens in 

 Salvatore's room, and sees the most delicate 

 and sensitive creatures- — corals, alcj'onaria, 

 transparent medusae, and ctenophores — fixed 

 in the fully expanded condition, and preserved 

 in their natural shape. This result is obtained 

 by a diff"erent method for almost every animal ; 

 and the successful treatment has been discov- 

 ered, sometimes by a fortunate idea, but usual- 

 ly by patient and careful series of experiments. 



THE SPECTRUM OF AN ARGAND 

 BURNER.^ 



I HAVE been lately requested to determine 

 the distribution of energ}- in the spectrum of 

 an argand burner, and have been able to do 

 this hj means of the apparatus and methods 

 previousl}' employed at the Allegheny obser- 

 vator}' for mapping the invisible spectrum of 

 the sun. The results are curious ; and, in the 

 hope that they maj' also be found useful, I 

 desire to communicate them to the academj'. 

 The difficulty in such a determination Hes in 

 the mapping of something which is wholly 

 invisible ; and it has not been made before, I 

 presume, in spite of its economical impor- 

 tance, because there has been no means known 

 of measuring this invisible energj', except in a 

 rough way, bj' the thermometer or thermo- 

 pile, by a process which gives incomplete re- 

 sults. 



It was m}^ object not merely to indicate 



1 Read before the National academy of sciences at its AVash- 

 iDgton meeting, April, 1883. 



