FEBRUARY 8, 1884.] 
assume that the position which an air-ship ought to 
occupy should be such that its major axis may make 
with the line of the wind an angle of several degrees. 
After the experiments we have just described, we 
stopped the motor, and the balloon passed over Mont- 
Valérien. Once, when it had taken the direction of 
the wind, we began again to turn the screw, proceed- 
ing this time with the current. The speed of the bal- 
loon was increased, and by means of the rudder we 
were now easily able to turn to the right or left from 
the line of the wind. We proved this by taking, as 
before, some point on the surface; and several spec- 
tators also verified it. 
At thirty-five minutes past four we made the de- 
scent in a large plain near Croissy-sur-Seine. The 
operation of landing was conducted by my brother 
with great success. We left the balloon inflated over 
night, and the next day it had not lost the least gas. 
Painters and photographers were enabled to obtain 
views of our air-ship, which was surrounded by a 
numerous and sympathetic assembly which the novel 
sight had attracted from all sides. 
We had intended to make a new ascent on this 
day: but, on account of the cold of the night, the 
bichromate of potassium in our ebonite tanks had 
crystallized; and the battery, which was by no means 
exhausted, was on this account, however, incapable 
of action. We drew the balloon to the shore of the 
Seine, near the bridge of Croissy; and there, to our 
great regret, we were obliged to discharge the gas, and 
to lose in a few instants what had required so much 
care in its preparation. 
Without describing in greater detail our return, we 
have concluded from this first trial that, 1°, electricity 
furnishes a balloon with the most convenient power, 
the management of which in the car is remarkably 
Casy; 2°, in our own case, when our screw, 2.8 
metres in diameter, made a hundred and eighty 
revolutions per minute, we were able to keep head 
to a wind moving three metres per second, and, when 
proceeding with the current, to deviate from the line 
of the wind with great ease; 3°, the mode of sus- 
pension of a car from an elongated balloon by means 
of bands running obliquely, and supported by flexi- 
ble side-shafts, insures perfect stability to the whole. 
We ought to say that our ascent of Oct. 8 should 
be considered only as a preliminary trial, which will 
be repeated with the alterations which our experience 
commends. In addition, we would mention that 
there was in the car a considerable excess of ballast, 
and that eventually it will be possible for us to use a 
much more powerful motor. Aerial navigation will 
not be made practicable through a single attempt: it 
will require many trials and efforts and great perse- 
verance under every ordeal. 
(To be continued.) 
ZHE DISCOVERY OF THE GERM OF 
SWINE-PLAGUE. 
Iy a communication read before the Paris academy 
of sciences, Nov. 26, 1883, by M. Pasteur, the follow- 
ing paragraph occurs: — 
SCIENCE. 
155 
‘As soon as [ received his [Thuillier’s| first letters from the 
commune of Peux, in the department of Vienne, it was certain 
that he had perceived in the blood and humors of the dead hogs 
a new microbion which it seemed should be the author of the 
disease. This microbion had escaped the observation of Dr. 
Klein of London, in the course of a long and remarkable ac- 
count of autopsies and experiments published three years before 
in the report of the English sanitary office. Dr. Klein stated 
that a microbion was the cause of the affection; but he committed 
an error, for the microbion that he described has no connection 
with the cause of vowget. Thuillier by his observation had over- 
come the principal difficulty to a knowledge of this disease of 
the hog. Historic truth, however, obliges me to declare, that in 
1882, and also in the month of March, the microbion of vouget 
was signalled at Chicago, in America, by Professor Detmers, in a 
paper which does great honor to its author. ‘Thuillier could not 
have been acquainted with this paper, and I myself only learned 
of its existence very recently. The observation of the microbion 
of rouget of the hog by Thuillier dates from the 15th of March, 
1882.” 1 
It is so very seldom that investigations on this side 
of the water receive any notice whatever abroad, 
and particularly in France, that it seems a pity even 
to call attention to the very great injustice done to 
American work in the above statement, since any 
recognition at all is so much better than being quietly 
ignored. There is, however, so much of general in- 
terest in regard to the gradual development of our 
knowledge of the germ of this disease, so much of 
interest in the success and failures of those who have 
worked upon it, that, aside from our desire to see his- 
tory correctly written, there is sufficient incentive for 
tracing the progress of this study, which commenced 
when the first real light was breaking upon the germ- 
theory of disease. 
Dr. Klein deserves more credit for his share in the 
discovery of the micrococcus of swine-plague than 
M. Pasteur seems inclined to grant. In 1876 he 
published one of the first, if not the very first, relia- 
ble microscopic studies of this disease. ‘The care 
and skill shown in this investigation are more appar- 
ent to-day than when the details were first published; 
and, although he subsequently made the unfortunate 
mistake of attributing the cause of the disease to a 
bacillus, this fact should not be allowed to weigh 
against his former and really valuable researches.? 
In his account of the microscopic appearances of 
the intestine, the following sentence occurs: — 
‘‘Hrom and even before the first signs of necrosis of the mu- 
cosa, viz., when the epithelium begins to break down and be 
shed from the surface, there are found masses of micrococci, 
which in some ulcers occupy a great portion of the débris.”5 
A little farther on he says, — 
‘There is one more point which I believe deserves careful at- 
tention. In the ulceration of the tongue just mentioned, and at 
a time when the superficial scab has not become removed, I have 
seen masses of micrococci situate chiefly in the tissue of the 
papillae, but at some places reaching as far deep as the inflam- 
1 La vaccination du rouget des porcs a Vaide du virus mortel 
atténué de cette maladie. PASTEUR et THUILLIER. Comptes 
rendus, Xevii. p. 1164. 
? Report on the so-called enteric or typhoid-fever of the pig, 
by Dr. Kien. In Reports of the medical officer of the privy 
council and local government board. New series, No. VIII. 
teport to the Lords of the council on scientific investigations, 
etc., 1876, pp. 91-101. 
3 Joe. cit., p. 98. 
