art of making observations and experiments, whi

OF MINUTE

last advances towards precision require a greater devotion of time, labour, and expense, than those which precede them. The first

most minute, and the accordance amongst them most perfect. It may, perhaps, be of some use to show, that even with large instruments, and most practised observers, this is but rarely the case. The

able to estimate how much of that OCCASIONAL DISCORDANCE FROM THE MEAN, which attends EVEN THE MOST CAREFUL OBSE

re, which is the more important, from the statement it contains relative

S SOINS LES PLUS ATTENTIFS N'EN SAUROIENT PRESERVER LES OBSERVATEURS LES PLUS EXERCES, et celui qui ne produiroit que des angles toujours parfaitment d'a

ature in such circumstances, that she is forced to record her minutest variations on so magnified a scale, that an observer, possessing ordinary faculties, shall find them legibly written. He who can see portions of matter beyond the ken of the rest of his species, confers an obligation on them, by recording wh

ON THE ART

iar with the subject, that in observations demanding no unrivalled accuracy, the principles of common sense may be safely trusted, and that any g

instruments, and having set the instrument at hazard, to write down the readings of the verniers, and then request his friend to do the same; whenever there is any difference, he should carefully examine the doubtful one, and ask his friend to point

ite down the result; then displace the telescope a little, and adjust it again. A series of such observations will show the confidence which is due to the observer's eye in bisecting an object, and also in reading the verniers; and as the first direction gave him some measure of the latter, he may, in a great measure, ap

him take the altitude of some fixed object, a terrestrial one, and having registered the result, let him derange the adjustment, and re

BJECT UNDER THE SAME CIRCUMSTANCES. It is only from a knowledge of this, that he can have confidence in his measures

own the reading of the vernier, and then let him derange the UPPER adjustment ONLY, re-adjust, and repeat the reading. When he is satisfied about the limits within which he can make that adjustment, let him do the same repeatedly with the low

In fact, both the time occupied in causing the extremities of the fingers to obey the volition, as well as the time employed in compressing the flesh before the fingers acted on the stop, appeared to influence the accuracy of our observations. From some few experiments I made, I thought I perceived that the rapidity of the transmission of the effects of the will, depended on the state of fatigue or health of the body. If any one were to make experiments on this

N THE FRAUDS

serve the thanks of all who really value truth, by stating some of the methods of deceiving practised by unwort

own, except to the initiated, and which it may perhaps be possible to render quite intelligible to or

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

, 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 coas

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

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 givi

s of the occurrence

fer most in excess from the mean, and in sticking them on to those which are too small; a spec

rvations 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

f which is to give to ordinary observations the appearanc

ect those only which agree, or very nearly agree. If a hundred observations are made, the co

l possess, is to calculate them by two different formulae. The difference in the constants employed in those formulae has sometimes a most

cific 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 judgme

other catalogues the difference would have been considerable, it is very unfair to accuse him of COOKING; for-those catalogues may have been notoriously inaccur

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;

se who cook, although they may perhaps not receive the attention which

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

ght 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 n

a 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 Floren

s 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 effe