On the frauds of observers.
Scientific inquiries are more exposed
than most others to the inroads of pretenders; and
I feel that I shall deserve the thanks of all who
really value truth, by stating some of the methods
of deceiving practised by unworthy claimants for its
honours, whilst the mere circumstance of their arts
being known may deter future offenders.
There are several species of impositions
that have been practised in science, which are but
little known, except to the initiated, and which it
may perhaps be possible to render quite intelligible
to ordinary understandings. These may be classed
under the heads of hoaxing, forging, trimming, and
cooking.
Of hoaxing. This,
perhaps, will be better explained by an example.
In the year 1788, M. Gioeni, a knight of Malta, published
at Naples an account of a new family of Testacea, of
which he described, with great minuteness, one species,
the specific name of which has been taken from its
habitat, and the generic he took from his own family,
calling it Gioenia Sicula. It consisted of two
rounded triangular valves, united by the body of the
animal to a smaller valve in front. He gave figures
of the animal, and of its parts; described its structure,
its mode of advancing along the sand, the figure of
the tract it left, and estimated the velocity of its
course at about two-thirds of an inch per minute.
He then described the structure of the shell, which
he treated with nitric acid, and found it approach
nearer to the nature of bone than any other shell.
The editors of the ENCYCLOPEDIE METHODIQUE,
have copied this description, and have given figures
of the Gioenia Sicula. The fact, however, is,
that no such animal exists, but that the knight of
Malta, finding on the Sicilian shores the three internal
bones of one of the species of Bulla, of which some
are found on the south-western coast of England, [Bulla
lignaria] described and figured these bones most accurately,
and drew the whole of the rest of the description
from the stores of his own imagination.
Such frauds are far from justifiable;
the only excuse which has been made for them is, when
they have been practised on scientific academies which
had reached the period of dotage. It should
however be remembered, that the productions of nature
are so various, that mere strangeness is very far
from sufficient to render doubtful the existence of
any creature for which there is evidence; [The number
of vertebrae in the neck of the plesiosaurus is a
strange but ascertained fact] and that, unless the
memoir itself involves principles so contradictory,
as to outweigh the evidence of a single witness,
[The kind of contradiction which is here alluded to,
is that which arises from well ascertained final causes;
for instance, the ruminating stomach of the hoofed
animals, is in no case combined with the claw-shaped
form of the extremities, frequent in many of the carniverous
animals, and necessary to some of them for the purpose
of seizing their prey] it can only be regarded as a
deception, without the accompaniment of wit.
FORGING differs from hoaxing, inasmuch
as in the latter the deceit is intended to last for
a time, and then be discovered, to the ridicule of
those who have credited it; whereas the forger is
one who, wishing to acquire a reputation for science,
records observations which he has never made.
This is sometimes accomplished in astronomical observations
by calculating the time and circumstances of the phenomenon
from tables. The observations of the second comet
of 1784, which was only seen by the Chevalier D’Angos,
were long suspected to be a forgery, and were at length
proved to be so by the calculations and reasonings
of Encke. The pretended observations did not
accord amongst each other in giving any possible orbit.
But M. Encke detected an orbit, belonging to some
of the observations, from which he found that all
the rest might be almost precisely deduced, provided
a mistake of a unity in the index of the logarithm
of the radius vector were supposed to have been made
in all the rest of the calculations. ZACH.
Corr. ASTRON. Tom. IV. p. 456.
Fortunately instances of the occurrence
of forging are rare.
TRIMMING consists in clipping off
little bits here and there from those observations
which differ most in excess from the mean, and in
sticking them on to those which are too small; a species
of “equitable adjustment,” as a radical
would term it, which cannot be admitted in science.
This fraud is not perhaps so injurious
(except to the character of the trimmer) as cooking,
which the next paragraph will teach, The reason of
this is, that the average given by the observations
of the trimmer is the same, whether they are trimmed
or untrimmed. His object is to gain a reputation
for extreme accuracy in making observations; but from
respect for truth, or from a prudent foresight, he
does not distort the position of the fact he gets
from nature, and it is usually difficult to detect
him. He has more sense or less adventure than
the Cook.
Of cooking. This is
an art of various forms, the object of which is to
give to ordinary observations the appearance and character
of those of the highest degree of accuracy.
One of its numerous processes is to
make multitudes of observations, and out of these
to select those only which agree, or very nearly agree.
If a hundred observations are made, the cook must
be very unlucky if he cannot pick out fifteen or twenty
which will do for serving up.
Another approved receipt, when the
observations to be used will not come within the limit
of accuracy, which it has been resolved they shall
possess, is to calculate them by two different formulae.
The difference in the constants employed in those
formulae has sometimes a most happy effect in promoting
unanimity amongst discordant measures. If still
greater accuracy is required, three or more formulae
can be used.
It must be admitted that this receipt
is in some instances rather hazardous: but in
cases where the positions of stars, as given in different
catalogues, occur, or different tables of specific
gravities, specific heats, &c. &c., it may safely be
employed. As no catalogue contains all stars,
the computer must have recourse to several; and if
he is obliged to use his judgment in the selection,
it would be cruel to deny him any little advantage
which might result from it. It may, however,
be necessary to guard against one mistake into which
persons might fall.
If an observer calculate particular
stars from a catalogue which makes them accord precisely
with the rest of his results, whereas, had they been
computed from other catalogues the difference would
have been considerable, it is very unfair to accuse
him of cooking; for—those catalogues
may have been notoriously inaccurate; or—they
may have been superseded by others more recent, or
made with better instruments; or—the observer
may have been totally ignorant of their existence.
It sometimes happens that the constant
quantities in formulae given by the highest authorities,
although they differ amongst themselves, yet they
will not suit the materials. This is precisely
the point in which the skill of the artist is shown;
and an accomplished cook will carry himself triumphantly
through it, provided happily some mean value of such
constants will fit his observations. He will
discuss the relative merits of formulae he has just
knowledge enough to use; and, with admirable candour
assigning their proper share of applause to Bessel,
to Gauss, and to Laplace, he will take that mean
value of the constant used by three such philosophers,
which will make his own observations accord to a miracle.
There are some few reflections which
I would venture to suggest to those who cook, although
they may perhaps not receive the attention which,
in my opinion, they deserve, from not coming from
the pen of an adept.
In the first place, it must require
much time to try different formulae. In the
next place it may happen that, in the progress of
human knowledge, more correct formula: may be
discovered, and constants may be determined with far
greater precision. Or it may be found that some
physical circumstance influences the results, (although
unsuspected at the time) the measure of which circumstance
may perhaps be recovered from other contemporary registers
of facts. [Imagine, by way of example, the state of
the barometer or thermometer.] Or if the selection
of observations has been made with the view of its
agreeing precisely with the latest determination,
there is some little danger that the average of the
whole may differ from that of the chosen ones, owing
to some law of nature, dependent on the interval between
the two sets, which law some future philosopher may
discover, and thus the very best observations may have
been thrown aside.
In all these, and in numerous other
cases, it would most probably happen that the cook
would procure a temporary reputation for unrivalled
accuracy at the expense of his permanent fame.
It might also have the effect of rendering even all
his crude observations of no value; for that part
of the scientific world whose opinion is of most weight,
is generally so unreasonable, as to neglect altogether
the observations of those in whom they have, on any
occasion, discovered traces of the artist. In
fact, the character of an observer, as of a woman,
if doubted is destroyed.
The manner in which facts apparently
lost are restored to light, even after considerable
intervals of time, is sometimes very unexpected, and
a few examples may not be without their use.
The thermometers employed by the philosophers who
composed the Academia Del Cimento, have been lost;
and as they did not use the two fixed points of freezing
and boiling water, the results of a great mass of
observations have remained useless from our ignorance
of the value of a degree on their instrument.
M. Libri, of Florence, proposed to regain this knowledge
by comparing their registers of the temperature of
the human body and of that of some warm springs in
Tuscany, which have preserved their heat uniform during
a century, as well as of other things similarly circumstanced.
Another illustration was pointed out
to me by M. Gazzeri, the Professor of Chemistry at
Florence. A few years ago an important suit
in one of the legal courts of Tuscany depended on
ascertaining whether a certain word had been erased
by some chemical process from a deed then before the
court. The party who insisted that an erasure
had been made, availed themselves of the knowledge
of M. Gazzeri, who, concluding that those who committed
the fraud would be satisfied by the disappearance of
the colouring matter of the ink, suspected (either
from some colourless matter remaining in the letters,
or perhaps from the agency of the solvent having weakened
the fabric of the paper itself beneath the supposed
letters) that the effect of the slow application of
heat would be to render some difference of texture
or of applied substance evident, by some variety in
the shade of colour which heat in such circumstances
might be expected to produce. Permission having
been given to try the experiment, on the application
of heat the important word reappeared, to the great
satisfaction of the court.