SCIENCE. 
325 
ed that the corresponding oxyphthalic acid has the follow- 
ing constitution, 
— COOH 
COOH 
V 
Nitrophthalic acid, melting at 165°, has the second (II) 
formula, while the one melting at 21 2°, has the first (1) 
formula. As stated above, these are both produced from 
mtronaphthaline, which is itself an a compound, and so 
it is demonstrated that the a position is the one next to 
the two common carbon atoms. The hydrogen atoms in 
naphthaline are ccmbined in groups of four, each of which 
is equivalent ; this follows naturally from the observed 
facts in benzols. 
Atterberg, in his masterly researches on the chlo- 
rinated naphthalines, found that in naphthaline, the 
four a positions are of equal value without any reference 
to the benzol formula. According to de Koninck, Mar- 
quardt and Atterberg, nitronaphthaline may be con- 
verted into a monochloronaphthaline. Therefore, in 
these compounds, the nitro and chloro groups hold the 
same position. The monochloronaphthaline may, how- 
ever, be converted into a nitro compound and that into a 
p dichloronaphthaline. Nitronaphthaline may be con- 
verted into two different dinitronaphthalines, and those 
into two different dichlornaphthalines y and Hence 
all three dichlornaphthalines p, y, contain a chlorine 
atom in the position of the nitro group of the nitronaph- 
thalines. The three remaining chlorine atoms of the 
three compounds must take different positions with refer- 
ence to the first, since otherwise the three compounds 
could not be different. All of the chlorine atoms of these 
compounds possess an a position, consequently the naph- 
thaline molecule must possess four a positions of equal 
value. 
DETERMINATION OF THE CONSTITUTION OF THE 
NAPHTHALINE DERIVATIVES. 
The constitution of naphthaline derivatives is ascer- 
tained by converting them by a simple reaction into 
another of known position. The nitro derivatives may, 
for instance, be converted into the chlorine or bro- 
mine derivatives by the chloride or bromide of phospho- 
rus, and then by reduction into the amido derivatives. 
These latter may, by means of their diazo-compounds, be 
converted into phenols, chlorine, bromine (and perhaps 
iodine) derivatives, and by means of formic acid into ni- 
triles, and consequently into carbon acids. The bromine 
derivatives produce, with ethyl and methyl iodide, ethyl 
and methyl compounds, and with chlorcarbonic acid 
ether carbon acids are produced. The sulpho-acids give 
with potassium cyanide, cyanates. With penta chloride 
and bromide of phosphorus, chlorine and bromine de- 
rivatives are obtained with sodium formate, carbon 
acids ; and with sodium at a high temperature phenols 
are formed. On the other hand the oxidation often shows 
whether the substituting groups are in the same ring, or 
are divided among both ; in the first case phthalic acid is 
fotmed, and in the second substitution products of phtha- 
lic acid are formed. 
In the case of the higher substituted naphthaline de- 
rivatives, the number ol possible isomers is considerably 
increased, especially when the groups are unequal. When, 
however, the groups are equal, fourteen tri-derivatives, 
twenty-two tetra-derivatives, fourteen penta-derivaties, 
ten hexa, two hepta, and a single octo-derivative, in 
which all the hydrogen has been replaced, are obtained. 
There are, for example, seventy-five possible chlorine 
naphthalines ; of these, however, only twenty-four have 
been prepared. In order to simplify the nomenclature of 
these numerous compounds, we will distiuguish the two 
from each other by designating the same position in each 
ing, as a >, a 2 , and P 2 . 
When a compound contains both of its substituting 
groups in the same ring, we will combine the latter after 
John’s method, that is, by a simple line, as for example, 
a!-/! 1 , a'-P 2 , a'-a 2 , etc. When, however, the groups are 
divided between the two rings, then they are combined by 
double lines, thus: a 1 — a 1 , a'=/P, a'—p 2 , etc. The same 
method of lettering may be used in the higher substituted 
compounds; thus the compounds a 1 —/? 1 — a 2 , a l —p 2 —a 2 , 
a'— /I 1 —/? 2 — a 2 , have their groups in the same ring. The 
compounds a 1 — a 2 =a', a 1 — a 2 =/j', a'^a 1 — a 2 , a 1 — a 2 =a 1 — p l , 
have their groups divided between the two rings. We 
have placed together, in a series of tables, the most im- 
portant derivatives of naphthaline. In these tables will 
be found their constitution as far as it is known ; some 
characteristic properties, as their melting point, boiling 
point, their formation, conversion, and, as complete as 
possible, a list of the literature. 
It is to be hoped that the many vacancies which 
appear among these tables may soon be filled. 
Last of all we would observe that the terms a, p, y, <5, 
etc., which we have chosen to represent the naphthaline 
derivatives have no connection with their constitution 
with the single exception of the mono derivative. They 
have been given to the different isomers only in chrono- 
logical order, and they do not correspond by any means 
as far as position is concerned to the different a, p, etc., 
derivatives. This fact is unfortunate, because it may 
cause confusion. We believe, however, that at present 
no change should be made in names originally chosen by 
the discoverers. When the constitution of the napthaline 
derivatives is better known, a rational nomenclature ac- 
cording to the above principals will naturally be adopted. 
Thus for instance the present p, y and f dichlornaph- 
thalines will be designated as a 1 — a 2 , a’=a 2 and a‘=a> di- 
chlornaphthaline.theaand A trichlornaphthaline as a 1 — P' — 
p 2 and a' — a 2 =a*, trichlornaphthaline, the a and p chloro- 
dinitronap'nthalines as — “ 2 = a 1 and — a 2 =a 1 chloro- 
dimitronaphthalines, and in a similar manner for all 
other compounds by which their constitution will be im- 
mediate!) recognized. 
CONSTITUTION OF THE NAPHTHALINE DERIVATIVES. 
The mono substitu:ion products exist in but two mod- 
ifications, and it is easy, therefore, to determine their 
constitution. When in the bisubstitution products, the 
two substituting groups are equal, ten different isomeric 
compounds are obtained. If, however, they are unequal, 
the number is increased to fourteen. The constitution of 
a given number of the same is exactly known, while with 
others it is only known that the substituting groups are 
contained in the same or in two different rings, that they 
possess an a or a p position, or a similar position. 
NATIONAL ACADEMY OF SCIENCES. 
The abstracts of the papers read before the recent 
meeting at New York were, in all cases, either corrected 
or rewritten by the authors, and we are under obligation 
to Professors James Hall, Wolcott Gibbs, E. D. Cope, 
S. P. Langley, Henry Morton, Elias Loomis, B. Silliman, 
O. N. Rood, T. Sterry Hunt, Henry Draper, for their 
assistance in presenting correct reports. 
The addresses of Professor Alexander Agassiz and 
Lieut. Shawatka were delivered viva voce, and we made 
use of the stenographic notes made for the New York 
