The siphon is supported on a vertical axle carrying two armatures which are acted upon by two electromagnets.
The rhodalome of some Rhodalidae, consisting of siphon, tentacle and one or more gonophores.
A Siphonophore is regarded as a single individual composed of numerous zoids, budded from the primary zoid (siphon) produced from the planula.
Screw adjustments are provided for closing or opening the air gap between the electromagnets and armatures, for raising or lowering the siphon, and for adjusting the point of the siphon to the centre or side of the paper strip. The received signals are recorded on the paper strip in an undulating continuous line of ink, and are distinguished by the length of deviation from zero.
Two receiving instruments, a siphon recorder and a mirror galvanometer, are shown; one only is absolutely necessary, but it is convenient Cable to have the galvanometer ready, so that in case of accident to the recorder it may be at once switched into circuit by the switch s.
A fine glass siphon tube is suspended with freedom to move in only one degree, and is connected with the signal-coil and moves with it.
The short leg of the siphon tube dips into an insulated ink-bottle, so' that the ink it contains becomes electrified, while the long leg has its open end at a very small distance from a brass table, placed with its surface parallel to the plane in which the mouth of the leg moves, and over which a slip of paper may be passed at a uniform rate, as in the spark recorder.
The ink is electrified by a small induction electrical machine E placed on the top of the instrument; this causes it to fall in very minute drops from the open end of the siphon tube upon the brass table or the paper slip passing over it.
When therefore the signalcoil moves in obedience to the electric signal-currents passed through it, the motion communicated to the siphon is recorded on the moving slip of paper by a wavy line of ink-marks very close together.
A very much simpler form of siphon recorder, constructed by Dr Muirhead, is now in general use.
33 shows a facsimile of part of a message received and recorded by a siphon recorder, such as that of fig.
- Facsimile of Siphon Recorder Message.
This device was converted into an electric wave detector as follows :-The mercury-steel junction was acted upon by the electromotive force of a shunted single cell and a siphon recorder was inserted in series.
When electric waves fell on the antenna they caused the mercury-steel junction to become conductive during the time they endured, and the siphon recorder therefore to write signals consisting of short or long deflexions of its pen and therefore notches of various length on the ink line drawn on the strip of telegraphic tape.
In the same way the arrangements finally elaborated by Lodge and Muirhead consisted of a direct coupled antenna and nearly closed condenser circuit, and a similar receiving circuit containing as a detector the steel wheel revolving on oily mercury which actuated a siphon recorder writing signals on paper tape.
The "Regency portable fountain," patented in 1825 by Charles Plinth, was the prototype of the modern siphon, from which it differed in having a stopcock in place of a spring valve.
The siphon is a simple instrument; but the forcing-pump is a complicated invention, which could scarcely have been expected in the infancy of hydraulics.
And most damaging, it can wage war and thereby siphon off wealth, technology, and the lives of its citizens.
In the undulator apparatus, which is similar in general principle to the " siphon recorder " used in submarine telegraphy, a spring or falling weight moves a paper strip beneath one end of a fine silver tube, the other end of which dips into a vessel containing ink.
It is in fact the electromagnet and spindle of a telegraph relay with a siphon in place of the tongue.
- Lord Kelvin's early Siphon Recorder.
The spark recorder in some respects foreshadowed the more perfect instrument - the siphon recorder - which was introduced some years later.
31), for which Lord Siphon Kelvin obtained his first recorder.
Instruments of the siphon recorder type have been made to work both with and without electrification of the ink.
1434 of 1899) it is sought to overcome this difficulty by causing the point of a contact-arm, representing the siphon in the ordinary form of recorder, to traverse the cylindrical surface of a rapidly rotating drum.
This magnet is excited by an alternating current, and the current induced in the second coil is after rectification sent through an ordinary siphon recorder.
As the direction and intensity of this induced current are a function of the position of the second coil in its field, and as this position is determined by its mechanical connexion with the recorder coil, it is evident that, by a suitable choice of the electrical elements of the second coil and its alternating field, the indications on the siphon recorder can be magnified to any reasonable extent.
E, Siphon with branched grappling tentacle, f.
A cormidium may contain a single nutritive siphon (" monogastric ") or several siphons (" polygastric ").
The athorome of Physophora, &c., consisting of siphon, tentacle, one or more palpons with palpacles, and one or more gonophores.
Thus a bract may be regarded, with Haeckel, as a modified umbrella of a medusa, a siphon as its manubrium, and a tentacle as representing a medusan tentacle shifted in attachment from the margin to the sub-umbrella; or a siphon may be compared with a polyp, of which the single tentacle has become shifted so as to be attached to the coenosarc and so on.
It must be pointed out that, however probable Haeckel's theory may be in other respects, there is not the slightest evidence for any such cleft in the umbrella having been present at any time, and that the embryological evidence, as already pointed out, is all against any homology between the stem and a manubrium, since the primary siphon does not become the stem, which arises from the ex-umbral side of the protocodon and is strictly comparable to a stolon.
Principal siphon, surrounded by gonosiphons, and these again by tentacles.
Physalia, general view, diagrammatic; B, cormidium of Physalia; D, palpon; T, palpacle; G, siphon; GP, gonopalpon; M d', male gonophore; M y, female gonophore, ultimately set free.
In the latter a pallial siphon, a welldeveloped proboscis and an unpaired oesophageal gland are always present, in the former they are usually absent.
The siphon is an incompletely tubular outgrowth of the mantle margin on the left side, contained in a corresponding outgrowth of the edge of the shell-mouth, and serving to conduct water to the respiratory cavity.
H', Prolonged siphonal notch of the shell occupied by the siphon, or trough-like process of the mantle-skirt.
Shell turriculated and siphonated, thick, each whorl with varices; foot broad and truncated anteriorly; pallial siphon well developed; proboscis present.
Shell turriculated, with elongated spire; proboscis short; siphon rudimentary.
Shell elongated, with long siphon; lateral teeth of radula multicuspidate.
Shell irregular; radula absent; foot and siphon short; sedentary animals, living in corals.
Head much flattened and wide, with eyes on sides; foot broad; siphon with internal appendages.
Foot very large; without operculum; shell with short spire and longitudinal ribs; siphon long.
Ampullaria has very long tentacles and a long siphon formed by the mantle.
The simple siphon is used by filling it with the liquid to be decanted, closing the longer limb with the finger and plunging the shorter into the liquid; and it must be filled for each time of using.
In the siphon used as a container for aerated waters a tube passes through the neck of the vessel, one end terminating in a curved spout while the other reaches to the bottom of the interior.
The hearth always has an Arents siphon tap. This is an inclined channel running through the sidewall, beginning near the bottom of the crucible and ending at the top of the hearth, where it is enlarged into a basin.
In the Greek school at Alexandria, which flourished under the auspices of the Ptolemies, the first attempts were made at the construction of hydraulic machinery, and about 120 B.C. the fountain of compression, the siphon, and the forcing-pump were invented by Ctesibius and Hero.
In this vessel is placed the short leg of a draw-off siphon, reaching to nearly the bottom.
The clear juice in the meantime flows over the edge of the cylindrical vessel without disturbance and finds its way out by the short leg of the siphon, and so passes to the canal for collecting the defecated juice.
Relay, Hughes, siphon recorder, &c.
- Muirhead's Siphon Recorder.