Besides investigating other phenomena connected with a vacuum, he constructed an electrical machine which depended on the excitation of a rotating ball of sulphur; and he made successful researches in astronomy, predicting the periodicity of the return of comets.
Manson showed in 1881 that the larvae (Microfilariae) were not at all times present in the blood, but that their appearance had a certain periodicity, and the larvae of F.
They, however, show no periodicity, and are found continuously both by day and by night; and their larval forms are termed Microfilaria perstans.
The conditions permit of the circulation of the alternating currents of low periodicity, which are used for operating the bells, but in respect of the battery the circuit is open until the subscriber lifts the receiver, when the hook switch, thus released, joins the transmitter with one winding of an induction coil in series across the circuit.
The periodicity shows itself in the form of an exacerbation of the still continuing fever, and that exacerbation may take place twentyfour hours after the first onset, or the interval may be only half that period, or it may be double.
Many chemists contributed to the establishment of such a periodicity, the greatest advances being made by John Newlands in England, Lothar Meyer in Germany, and D.
The relation between the atomic volumes and the atomic weights of the solid elements exhibits the periodicity which generally characterizes the elements.
There is no doubt about the latter variation, but with regard to its periodicity - that is, the number of years elapsing between one maximum and the next - much still remains to be done.
HellandHansen and Nansen traced a periodicity in the flow of Atlantic water along the W.
In this way it may happen that although there is almost perfect periodicity with each revolution of the screw after (say) loo lines, yet the loo lines themselves are not equally spaced.
In this case there is approximate periodicity in the half interval, but complete periodicity only after the whole interval.
He found out the formula for deriving the sine of a multiple angle, knowing that of the simple angle with due regard to the periodicity of sines.
John Goodricke established in 1782 the periodicity of its change in about 2 d 21 h, and suggested their cause in recurring eclipses by a large dark satellite.
Let it be represented by a displacement curve Ahbkc. Its periodicity implies that after a certain distance the displacement curve exactly repeats itself.
This want of proportionality will have a periodicity, that of the impinging waves, and so will produce vibrations just as does the variation of pressure in the case last investigated.
It was originally discovered in 1789, but its periodicity was not recognized until 1818, after it had been observed at several returns.
Of definite periodicity, and then also gives us the distribution of intensity along the homogeneous constituents.
The periodicity of the seasons usually allows two, and sometimes three, harvests in the year, but not necessarily, nor indeed usually, from the same fields.
He was one of the first, if not quite the first, to propound the conception of periodicity among the chemical elements.
Complete periodicity is only attained after the passage of a pair of drops; and thus the odd series of drops pursues one path, and the even series another.
Owing to the fact that the cylinder is losing or gaining slightly in speed on the circuit periodicity, the voltmeter goes slowly, say in one minute, through all the phases 1 E.
The females produce thousands of larvae, which circulate in the blood, and show a certain periodicity in their appearance, being much more numerous in the blood at night than during the day.
We have seen how its utilization in the " structure theory " permitted great clarification, and attempts were not wanting for the deduction of analogies or a periodicity between elements.
It is mainly because these fisheries are seasonal that the periodicity has been noticed, and because of the economic interests involved the study of the seasonal and longer periodicities has become very important.
Fritz, Das Polarlicht (Leipzig, 1881); (3) Svante August Arrhenius, Lehrbuch der kosmischen Physik; (4) Joseph Lovering, " On the Periodicity of the Aurora Borealis," Mem.
The varying brightness, ranging from the ninth to the second magnitude, was recognized in 1639 by John Phocylides Holwarda, and in 1667 Ismael Boulliau (1605-1694) established a periodicity of 333 days.
Up to 1890 the most careful observations and researches failed to establish the periodicity of such a rotation, though there was strong evidence of a variation of latitude.
The surface level of the lake varies with the season, and recent observations taken on behalf of the Palestine Exploration Fund seem to show that there are probably cyclical variations also (ultimately dependent on the rainfall), the nature and periodicity of which there are as yet no sufficient data to determine.