We shall first consider the pipe in a state of continued sonorous latter, only with great attention to the voicing, or adjustment of the vibration (no matter how produced), yielding the lowest note which it orifice through which the wind enters. If the bore of a flute be: will give : let it be a simple pipe open at both ends, and let it be sounding, too narrow (which we imagine to be the case in modern instruments), say the c of the treble clef, which note requires 258 double vibrations the lower notes will be difficult to obtain. And the various harmonics per second. If we now remember that the air at the two extremities are produced with very different degrees of facility; a circumstance of is in communication with the outer air, we see that no condensation or which the theory can give no account. Thus, players on the trumpet rarefaction can take place at those extremities, or only very small ones find it exceedingly ditficult to produce that tone which divides the compared with those which take place in the interior of the tube. To instrument into seven parts, or the flat seventh in the third octave get approximately at the conditions of vibration, let us suppose that above the fundamental note; while in the flute there is no moderately no condensation or rarefaction takes place at the extremities. We skilful player who cannot produce it. It is to be observed however then see (Acoustics] that the state of the pipe, its two extremities that all pipes of the trumpet class are of tapering diameter; and never being condensed or rarefied, is as it would be if two waves of though they agree in all material points with the theory of cylindrical sound were travelling in opposite directions, every particle of the and prismatic pipes, it is not remarkable, in the present state of the interior being affected by the joint condensations and velocities of mathematical analysis of this subject, that they should present circumboth. Moreover, the distance between two uncondensed particles is stances difficult of explanation. always the whole length of the wave of condensation or that of rare- It will be obvious, from the considerations in Acoustics, that when faction, or a multiple of this length; that is, the pipe must be either the extremities of the pipe contain between them n half-waves, there the half-length of a double wave or a multiple of this half-length. will be n + 1 points (the orifices included) at which the velocities are When the pipe sounds the lowest note, it must give the longest wave; always greater than elsewhere, and no condensations or rarefactions ; that is, the length of the pipe must be that of the simple wave of con- and n points (in the middle of the subdivisions), at which the condensadensation or rarefaction. Hence, the lowest note which a pipe can tions or rarefactions are always greater than elsewhere, and which are yield, which is called its fundamental note, is that belonging to a double always at rest or nearly so. These immoveable points are called nodes wave of sound which is double of its length. Each double wave of vibration; and there is one of them in the middle of the tube only answers to a complete or double vibration of a string,

when the number of half-waves in the pipe is odd. To compare this result with practice, let us suppose sound to Let us consider the case of a pipe with one end closed. It is obvious travel at the rate of 1125 feet per second (temperature 62° Fahr.). The now that the open extremity is a point of no condensation, while the note c having 258 double vibrations per second, this 1125 feet must closed extremity must be a node, or point of no velocity. Hence the contain 258 double waves, or each double'wave must be 4.36 feet. The tube must be the half of an odd number of simple waves in length, single wave then is 2.18 feet, or 2 feet 2 inches and 16 of an inch, twice the tube must be an odd number of simple waves, and four which is the theoretical length ‘of the pipe. Now the organ-builders times the tube an odd number of double waves in length. Hence say 2 feet (ORGAN, CONSTRUCTION OF], but this of course is a rough the fundamental note belongs to a double wave of four times the description, since the French organ-builders also say 2 feet (according length of the tube; so that the fundamental note of a pipe closed to Biot), and the French foot is longer than the English. Further on at one end is an octave lower than that of the same pipe open at in the article referred to we see 2 feet 2 inches given as the length of both ends. It is the same thing to say that a pipe of half the length this c in an open pipe (the dulciana), and 1 foot 1 inch in a stopped of an open pipe, closed at one end, gives the same note as the open pipe (the stopped diapason), which, as we shall presently see, ought to pipe. This is the reason why the pipes of the stopped diapason be half as long as an open pipe. The common flute, when everything stop of an organ are halves of the lengths of those of the open is stopped, gives this same c, and the length from the embouchure (or diapason. mouth-hole) to the end of the instrument is a little more than 2 feet, Again, since the double length of the pipe is an odd number of but certainly never 2 feet 2 inches. It must be remembered however simple waves, the harmonics which the pipe can yield are not the comthat this instrument is made up of the flute (so called) and the player, plete set yielded by the open pipe of double the length, but every whose lips, when they come over the embouchure, confine the air, and other one, beginning from the fundamental note. The number of are equivalent to a slight lengthening of the pipe. It is not the man- vibrations per second being 1, those of the harmonics producible by ner of blowing which does this, but the approach of the lips, as may the pipe closed at one end are 3, 5, 7, &c. We will leave the pipe be thus shown. 'Take a common flute, and without holding it to the closed at both ends (a matter of no practical concern, since its sound lips, strike the uppermost hole with the finger; a faint sound will be could not be heard) to the student; the result he should arrive at by heard. Now approach the lips to the embouchure, but without blow- the preceding considerations, is that it is in all respects analogous to ing, and then strike the same hole with the finger; another faint the vibrating Cord fixed at both ends. But he must not infer, by a sound will be heard, decidedly flatter than the former. It is well reversed analogy, that the vibrations of an elastic body fixed at one known to those who play on this instrument (to those who play in tune end (as the spring of a tuning-fork) answer to those of a pipe closed at at least) that drawing the lips back, so as not so much to confine the one end, since their law is very different. air contiguous to the embouchure, sharpens the tone, and what some It is usual first to give the theory of a closed pipe, and then to persons call humouring the instrument means continual alteration of suppose the open pipe made of two closed pipes, with their closed ends the position of the lips, so as to shorten or lengthen the pipe by turns, together, and their closing diaphragms removed. The opposition of according to the note to be sounded. It is also well known to players the vibrating movements will then keep the particles in the middle at that this humouring can be carried to a much greater extent with the rest. This is a sufficient explanation of those modes of vibration of high notes than with the low notes; but so little were the practical the open pipe in which there is a node in the middle. musicians in connection with the theoretical in the time of Daniel We now come to the explanation of the manner in which the Bernoulli (who first gave the mathematical theory of this subject), sonorous vibration of a pipe is maintained. If we suppose a vibrating that this simple fact was only discovered by him from a new and some body placed at the orifice, it is found that if the vibrations of the what complicated experiment.

body be equal or nearly equal to those of the fundamental note of the In the preceding theory all the parts of any section of the pipe per- tube in the preceding theory, or one of its harmonics, the sound of the pendicular to its axis are supposed to vibrate in the same manner. vibrating body is reinforced by the tube. A slight alteration of the This cannot be the case in the common flute or in the organ-pipe, tube, though it may sharpen or flatten the note, does not by any means in which the cause of condensation is supplied at the side ; and in fact produce such a difference as would be caused by the same alteration, all experiments in which the cause of undulation has been equally if the sound were caused by the tube alone. We do not intend to go applied over all the parts of a section perpendicular to the axis, have into this subject; the reader may find it discussed, both mathematically agreed in the result that the time of vibration is wholly independent of and experimentally, in a paper by Mr. Hopkins, published in the the diameter of the tube : while those in which the same was not fifth volume of the Transactions of the Cambridge Philosophical equally applied give the result that the greater the diameter the lower Society.' is the tone. Moreover, when an orifice is made in the side of a pipe, When the sound is caused by a current of air, as in the common as in the flute, it is not equivalent to the formation of a new pipe ter- fute or simple organ pipe, a tolerably satisfactory explanation of the minating at that orifice, though the results are somewhat resembling. phenomena has been given in the case of the pipe closed at one end (to Any note between the fundamental note and its octave may be which writers have confined themselves); but none whatever in that obtained by an orifice of one size or another made at or near the of the pipe which is open at both ends. In the former case, as in a middle of a pipe.

reed of the Pan's pipe, a current of air is directed laterally over the We have seen that we may suppose the extremities of the open pipe mouth of the pipe, with a slight obliquity of direction. A condensato contain between them 2, 3, &c., half-waves, which, the whole tion is therefore produced in the tube, which travels to the closed end, pipe being one half-wave in length, will give the Harmonics of the and is there reflected; so that by the timo the condensation has fundamental note. This subject is sufficiently treated in the article travelled over twice the length of the tube (down and back again), the cited.

whole condensation, such as it was when it began, is doubled. Hence Various instruments yield different harmonics more or less readily; the air in the tube has now become more powerful than the external the general rule being that the more violent the agitation which pro- stream, and the condensed portion begins to be discharged. This duces the sound, the larger the number of half-waves formed in the continues until not only the whole of the condensation is discharged, tube, and the higher the harmonic: also that a certain diameter, the but also until all the velocity of the issuing particles has been destroyed; larger the greater the length of the tube, is necessary to the produc- and this is not done until the effect of that velocity has produced a tion of the fundamental note. Thus, if an organ-pipe be too small in rarefaction in the tube. The effect of the condensation is destroyed in the bore, it will yield the octave of the fundamental noto; or if the the same time as that in which it was produced; and hence the com.

a

PIPERINE

PIPE.

535

open tube.

C-1

plete undulation belonging to the whole length of the closed tube is The strength of a pipe must be such as to ensure its resistance to four times the length of the tube. Imperfect as the preceding the external and internal pressures it is likely to be exposed to; but, explanation is, we know of no way of applying even so much to the if it should work under pressure, the internal force will be, generally

speaking, so much in excess of the external one, that it will suffice to

The It is also to be noted that the whole of the preceding theory is but consider the former condition to the exclusion of the latter. an approximation. The extremities of the open tube are not points of usual formula for calculating the thickness of pipes is as follows: absolute non-condensation and non-rarefaction, but points at which the calling P, the pressure per square inch; r, the radius in inches of the condensations and rarefactions are least and small. Similarly the nodes interior diameter; and c, the cohesive strength of the metal per are not points in which the air is absolutely at rest, but points at which

pr the motion is least. The extensions of this theory, however, important square inch; then x = : Mr. Hawksley adopts a rather simpler as they are in a physical point of view, are not essential to that fundamental explanation of the musical phenomena of a pipe, to which formula, namely: x = 0·18 Vd; in which d = the diameter in inches. we have expressed our intention of confining ourselves in the present In practice, however, the theoretical thicknesses attained by either of article.

these formulæ are exceeded, on account of the difficulty of securing good PIPE, a circular or square artificial channel for the conveyance of sound pipes, when the thickness is very small. Stone and earthenwatery fluids, either under pressure, or flowing freely, or for the ware pipes being usually made of large diameters, and being exposed to passage of æriform fluids, or of sound. According to the almost endless great external pressures and jars, seem to require greater thicknesses varieties of uses to which pipes may be converted, and to the positions than are usually given to them; perhaps when their diameter exceeds in which they may be placed, the materials of which they are formed 9 inches they ought, in the present state of the arts, to be made of may be modified in an equally varied manner. A few of the more such a thickness that the latter dimension should be equal to Ith of prominent uses, and of the more generally adopted materials, are the diameter at least. therefore all that it will be possible here to allude to, under the Rain-water, or other metal descent-pipes are made with projecting general name of pipes.

ears upon the socket ends, for the purpose of receiving the nails by For the purpose of removing rain-water from buildings the ancients, which they are to be fixed one above another. In these cases the end and even occasionally the moderns also, have resorted to the use of joints are not required to be fitted hermetically. earthenware pipes of ordinary clay baked in kilns, but of late years PIPE-OFFICE, or more properly the Office of the Clerk of the lead, zinc, or iron pipes have been used in preference either to the Pipe, an ancient office in the Exchequer, abolished with that of compearthen, or the stoneware pipes. Copper pipes are commonly used for troller of the pipe, by 3 & 4 William IV., c. 99. The records of the the ascending pipes from force pumps; but the distribution of water office were then transferred to the custody of the king's rememhorizontally is almost always effected through cast or wrought iron, lead, brancer. See the Report of the Commissioners on Public Records, or tin pipes. Gas is distributed through cast iron mains, wrought iron 1837, p. 198. service-pipes, or through small pipes of tin, or of inixed metal with a PIPER, MEDICAL PROPERTIES OF. Pepper. According to the tin base. The foul waters from modern houses are removed through analysis of Pelletier, black pepper contains an acrid soft resin, a volaglazed stoneware drains, whilst land drainage waters are removed by tile oil, piperine, extractive, gum, bassorine, malic, and tartaric acids, means of red earthenware pipes. Until within a very few years the salts, &c. White pepper is the same fruit deprived of its outside whole of the water supply of our towns was carried through elm pipes; rind. and at the present day wood is still used for conveying water in The odour of pepper is probably due to the volatile oil, which is not agricultural districts, whilst that material is considered to be the most acrid; the pungent taste is most likely owing to the resin. Piperine is fitted for the conveyance of such fluids as tan liquor, or the bilge generally yellow, from the presence of some resin, to which it is most waters of ships. Indian rubber and gutta percha pipes are some probably indebted for its virtues, as when purified by means of ether from times used for garden and irrigation purposes; and leather pipes are all resin, it seems devoid of power, and the febrifuge virtues ascribed almost universally used for fire engines, or for moveable pumps, of any to it belong in reality to the acrid resin. Pepper is much more emkind.

ployed as a grateful condiment than as a medicine, and it appears to Smoke, hot air, and hot water are conducted through pipes or be essential to the process of digestion in hot countries. Of 50,000,000 channels formed, as the case may require, of ordinary bricks; of pounds of pepper collected, one-third only goes to Europe, the greater moulded bricks, of glazed brick, or stoneware pipes; or of cast or portion being consumed by the Chinese. Its moderate use with cold wrought iron, or of copper, zinc, lead, or tin; and in the construction raw vegetables or other substances difficult of digestion is to be apof boiler furnaces, of drawn brass. Sound is conveyed through metal proved; its employment in excess is hurtful to the liver, and a very pipes, or through Indian rubber, or gutta percha tubes.

large dose may prove fatal, not only by exciting inflammation of the
The stoneware and cast iron pipes certainly are the most durable stomach, but by an impression on the nervous system. Black pepper
under ground; but the chemical natures of the fluids conveyed, and of readily poisons hogs.
the ground itself, vary within so wide a range as to render it necessary Whole pepper is a popular remedy against intermittent fevers, and
to exercise great circumspection in the choice of the materials to be impure piperine is used beneficially in like cases.
used. Every case must in fact be regarded on its own merits ; Piper betle and piper siriboa, besides the use of them in chewing,
observing simply that metals are peculiarly liable to decay under the are also employed, in the form of the freshly expressed juice, as a
continuous action of dilute acids; and that such decay will be accele- febrifuge medicine, and as an antispasmodic, especially against obsti-
rated if any galvanic action should be superinduced. In earth, it may nate dry coughs.
be taken as a general rule that stoneware pipes will last longer than Piper methysticum, by fermentation, yields a powerfully intoxicating
metal ones ; that lead will last longer than cast iron, and much longer drink. Matico is yielded by a plant called Artanthe elongata, formerly

;
than wrought iron or wood; and that both on the score of their rapid considered a species of piper. [Matico.]
decay in such positions, and of their compressibility, the pipes made PIPERIDINE. [PIPERINE.]
from vegetable substances, such as gutta percha or Indian rubber, PIPERINE (CH2 N 0,2 ?). An alkaloid contained in the different
are 'very objectionable for use in the ground. [SEWERAGE; Water varieties of pepper. [PIPER, in Nat. Hist. Div.] It was discovered
SUPPLY.]

by Oersted in 1819, and is best obtained by the following process.
Cast iron pipes are cast vertically in loam moulds; wrought iron White pepper, coarsely comninuted, is digested in alcohol, the
pipes are either lapwelded or brazed ; lead pipes are either soldered on latter recovered by distillation, and the residual extract treated with a
their longitudinal seams, or they are forced by hydraulic pressure upon small quantity of solution of potash to remove resinous matter; the
a mandril, so as to ensure their perfectly homogeneous character; tin resulting impure piperine is washed with water and obtained pure by
pipes, and copper or composition pipes are usually brazed, but in one or two recrystallisations from alcohol. Piperine occurs in colour-
unimportant works their longitudinal joints may be soldered like less prisms, it is insoluble in cold water, only slightly so in hot water,
those of the lead pipes. The end joints of cast iron pipes are either tolerably soluble in ether, and readily so in alcohol, the essential oils,
made with a spigot and faucet joint, which may be either turned so as and acetic acid. Heated to about 212° Fahr. it melts, and at a higher
to fit quite tight, or be left large enough to receive a packing of yarn, temperature decomposes. Concentrated sulphuric or hydrochloric
white lead, and melted pig lead; or they are made with flange joints acids dissolve it, and nitric acid oxidises it to a brown coloured sub-
connected by means of bolts and washers. The ends of wrought iron stance, that dissolves in caustic potash with production of a beautiful
pipes may be connected by means of screw couplings, or by flanges; blood-red colour.
and the end joints of the more easily soldered materials are made by Piperine is but a feeble base. It absorbs hydrochloric acid gas with
that process, taking care of course to provide against the irregularities avidity, a stable hydrochlorate being formed. The chloroplatinate
of contraction, or of expansion in the pipes. It is precisely on account (C6H3N,022, HCI, PtCl,) forms large orange-coloured crystals, very
of the play afforded by the spigot and faucet joints of cast iron pipes, soluble in water or alcohol.
that they are adopted when any danger of changes of temperature Piperidine (C.,,N) is obtained when one part of piperine is dis-
exists. As it is not possible to make a screwed joint with any tilled with three parts of potash-lime. It is a light oily body that rises
description of earthen pipes, those articles are always made with to the surface of the distillate on the addition of solid hydrate of
spigot and faucet joints. The end joints of gutta percha and of potash. It is volatile, boiling at about 222.8° Fahr., colourless when
Indian rubber tubes are melted, and both the longitudinal or the end pure, has a powerful amnioniacal odour, and is very soluble in water.
joints of leather pipes are sewn or riveted; wood pipes have turned Its constitution has not yet been satisfactorily ascertained ; it is usually
and bored joints fitting into each other, which are sometimes screwed looked upon as ammonia in which two equivalents of hydrogen are
together,

replaced by the diatomic radical piperyl (CH.." or Pp”). Piperyl

12

38

11

537

PIPERYL-BENZAMIDE.

may however be a compound, and contain two radicals (C, H, + C10-
H10-), each capable of taking the place of an equivalent of hydrogen
in ammonia.
Piperidine forms crystalline compounds with most of the acids.
The hydrochlorate (C,H,,N, HCl) occurs in long colourless needles
very soluble in water. The oxalate (2 CH1N, CO, 2 HO) also forms
Piperyl urea, or the cyanate of piperidine (C, (H, Pp") NO or N(H,
Pp"), O, CyO), is formed on boiling a solution of sulphate of piperidine
with one of cyanate of potash; it may be obtained in long white

delicate needles.

needles.

Methyl-piperyl urea (N (H, C,H,, Pp") 0, CyO) and ethyl-piperyl urea (N(H, CH, Pp") O, CyO) are produced by acting upon piperidine with the cyanates of methyl and of ethyl respectively.

By the action of the iodides of the alcohol radicals upon excess of piperidine the following bases are produced. They are oily liquids, have fixed boiling points, and form well defined crystalline salts with acids :

Methyl-piperidine
Ethyl-piperidine

Amyl-piperidine.

SC2H3
N
Pp"

Excess of the alcohol iodide gives rise to iodides of the following ammoniums. By the usual oxide of silver method these iodides yield hydrated oxides :—

N(CH3)2Pp"
N(CH3)2Pp"

Piperyl-sulphocarbamic acid. Bisulphide of carbon combines energetically with piperidine (Cahours) :

C2+2C10H11N

=

C22H22N2S

whilst at night they should have the highest ground before them, in
selves seen. The duties of officers in command of piquets is to give
order to see an approaching party against the sky without being them-
immediate information of any signs indicating the intention of the
enemy to make an attack, such as a strengthening of the outposts,
Should an attack be made, the object of the piquets is by all means in
unusual movement of troops, noise of artillery on the march, &c.
their power to gain sufficient time to enable the main body in their
It is not the object of
rear to get under arms and prepare for action. Hence the posts should
defend as long as its flanks are not attacked.
be strengthened by breastworks, abbatis, &c., which the piquet should
piquets that they should defend themselves to the last, or shutting
should retire steadily on the main body, disputing every available
themselves up in a house or enclosure be cut off, but rather that they
obstacle; but, at the same time, in an extreme case an officer must
remember that it is his duty to sacrifice himself rather than be driven
in on the main body before it has had time to form.

PIRACY (immediately from the Latin pirata, and remotely from the Greek Teipaths) or robbery and depredation on the high seas, is an offence against the universal law of society; a pirate being, as Blackstone expresses it, "hostis humani generis." "With professed pirates," Lord Stowell observes (2 Dods., 244), "there is no state of peace. They are the enemies of every country, and at all times; and therefore are universally subject to the extreme rights of war."

Molloy, an ancient writer on maritime law, but whose doctrine it "If a piracy be would be dangerous to adopt in these days, says, immediately punish them with death, and not be obliged to bring attempted on the ocean and the pirates are overcome, the captors may them into any port, provided this occurs in places where no legal judg ment can be obtained. So likewise if a ship be assaulted by pirates, and in the attempt they are subdued and taken, and carried into the next port, if the judge openly rejects their trial, or the captors cannot wait till judgment shall be given without certain peril and loss, they may do justice on them themselves without further delay or attend'De Jure Maritimo,' chap. iv., sect. 12, 13.) (Molloy, "There is said to be a fashion in crimes; and piracy, at least in its simple and original form, is no longer in vogue. There was a time when the spirit of buccaneering approached in some degree to the

Gerhardt thinks the product may be piperyl-sulphocarbamate of spirit of chivalry in point of adventure; and the practice of it, parpiperdine, viz. :—

C22H22N2S

ticularly with respect to the commerce and navigation and coasts
of the Spanish American colonies, was thought to reflect no dis-
honour upon distinguished Englishmen who engaged in it. The grave
judge (Scaliger) observes, in a strain rather of doubtful compliment,
Nulli melius piraticam exercent quàm Angli.'" (Lord Stowell, 2‹
Dods., 374.)

The offence of piracy, by the common law of England, consists in committing those acts of robbery and depredation upon the high seas,

Pp" formed from piperidine and which, if committed upon land, would have amounted to felony there.

Piperyl-cuminamide (NPH, O.

11

chloride of cumyl, crystallises in tables.
PIPERYL-BENZĂMIDE. [PIPERINE.]
PIPERYL-CUMINAMIDE. [PIPERINE.]
PIPERYL-SULPHOCARBAMIC ACID. [PIPERINE.]

PIPERYL-UREA. [PIPERINE.]

PIQUETS, or PICKETS. All armies and smaller bodies of men, in camp or bivouac, are protected against surprise by small detachments of troops termed piquets, thrown out on their front and flanks. There are two descriptions of piquets, the outlying and inlying piquets, whose strength depend of course on the length of front to be watched and the liability of attack. The outlying piquet is advanced a considerable distance in front of the camp, while the inlying piquet generally remains in camp ready accoutred to turn out at a moment's notice to support the outlying piquets: communication between the two sets being maintained by sentries conveniently posted for hearing and observing any alarm in front, and if necessary by patrolling to the advanced posts. The general duties of the outlying piquets are to insure the safety and repose of the camp, to gain intelligence of the enemy's movements as early as possible, and even of his intentions by examining the peasantry, and to prevent his making reconnaissances; with this object they are posted with a chain of double sentries in front, on the same principle that light troops are extended to cover a line, with supports in their rear, and if far from the main body with a reserve also. Each company on piquet is divided into three reliefs, one relief being extended on sentry while the other two are in support, the sentries being relieved every hour during the night. As a further precaution against surprise, and as a means of obtaining information, frequent patrolling is directed along the front of the line of sentries, and, if the enemy's posts be far off, along the roads in their direction, as far as is deemed expedient. These patrols are preceded by feelers, quick intelligent men; and, avoiding all unnecessary firing, so as not to create false alarms, retire steadily, and if possible unobserved, on the piquets, on finding themselves in presence of the enemy. A strong patrol should always be sent out about an hour before daylight, when the whole of the advanced piquets are also got under arms, as this is the time when an attack is most likely to be made; for this reason, also, piquets are generally relieved at this hour, as a great accession of force is thus obtained. In the daytime the sentries should be on high ground, the better to observe the enemy's movements;

But by various statutes other offences are made piracy, especially dealing in slaves. (See on this point, Blackst. 'Com.' Mr. Kerr's ed., vol. iv.; and Abbott, On Shipping,' 140, 141, 142, 239.)

Persons guilty of piracy were formerly tried before the admiralty court, according to the rules of the civil law. This was altered by the statute 28 Henry VIII., c. 15, which enacted that the trial should be before commissioners of oyer and terminer, and that the course of the proceedings should be according to the common law. Further provision was made by the statutes 39 Geo. III., c. 15; 43 Geo. III., c. 113; 46 Geo. III., c. 54; and now, by the stat. 4 & 5 Wm. IV., c. 36, sec. 22, the trial of offences committed on the high seas is before the Central Criminal Court, or the judges at the assizes.

PISCES (the Fishes), the last constellation of the old zodiac. There is in the mythological stories (which are unworthy of note) a confusion between this constellation and Piscis Australis, presently to be noticed. (See Grotius, in his notes on Aratus.) The constellation consists of two fishes linked by a string attached to their tails: they are not close together, the upper one being close to Andromeda, the lower one under the wing of Pegasus. The rectangular figure mentioned in PEGASUS will be a guide to the position of the two fishes: the line of a Andromedæ and y Pegasi being parallel to the body of one fish, and that of y Pegasi and a Pegasi to the body of the other. The principal stars are as follows:

northern border of the table-land, like the country around Bukhara general way, be compared with those of the Indian peninsula and South or Bucharia, lies at a very small elevation, probably not more than America, but with this difference : the Western Ghauts in the former, 1000 or 2000 feet above the sea, while the surface, as we know, and in and the Cordilleras of the Andes, present their principal acclivities agreement with a previous statement in this article, descends on the towards the west, and thence slope gradually eastwards ; whereas the borders of the Caspian to 80 feet below that level.

African plateau rises abruptly on its eastern side, and has its western The table-land of Tibet itself is the summit of a great protuberance counterslope towards the interior of the continent and the valley of the above the general level of the earth's surface, of which the Kouenlun Nile. Another point of difference is, that while the rivers which rise and Himalaya are the north and south faces, while the other mountain- near the western edge of the Ghauts and of the Andes take their ranges and intervening valleys commonly marked on our maps of courses eastwards over the counter-slopes, at right angles with the Tibet are but corrugations of the table-land more or less strongly water-parting (commonly called the water-shed) [WATER-Sued] or marked. In its general relief, however, the table-land is laid out hori- nearly so, and discharge their waters into the ocean—the streams zontally, at a mean elevation of 15,000 feet. The Indus and Brahma- which have their sources at the water-parting of eastern Africa pootra rivers maintain a course along the length of the summit of the flow in a general north-westerly direction, and fall into the Nile, table-land, and receive as they proceed the drainage of its entire which skirts the lengthened western counter-slope. To these combreadth, with the exception, first, of an occasional strip along its parisons of Dr. Beke, it may be added that the general structure of the southern edge, from which the water passes oft

' more or less directly to | African plateau resembles that of Tibet, described above. While the north through the Himalaya; and secondly, of some parts chiefly the principal direction of the latter, however, is from east to west, found in the northern half of the table-land, from which the water has its slopes being on the north and south-the principal direction no escape, but is collected in lakes in depressions on its very summit. of the former, as we have seen, is from north to south, the slopes The waters accumulated in these two streams are at length discharged being on the east and west. But, mutatis mutandis, accordingly, the by two openings in the Himalayan slope, through the plains of Hindos- resemblance between the great table-lands of Africa and Asia is tan, into the Indian Ocean. None of the drainage of the table-land, so closer, we think, than that of the former to the elevated country far as is known, passes in the opposite direction through the northern bounded by the Ghauts and the Cordilleras respectively. In this slope. The waters of that slope itself exclusively flow down to the comparison the Indus and the Brahmaputra correspond to the Nile plains of Yarkend.

itself, while their main tributaries, the Jumna, Ganges proper, &c., That portion of the table-land which forms a plain along the upper answer to the streams which fall into the Nile, as already mentioned, course of the river Sutlej, we are informed by Major R. Strachey (to from the south-east. The structural resemblance between the tablewhose researches, and those of his brother Captain H. Strachey, much lands of the two great continents is also very near in another respect, of our present accurate knowledge of these regions is due),“ lies imme- allowing for the different distribution of dimensions. In the southern diately to the north of the British provinces of Kumaon and Gurhwal, extension of the African plateau, the rivers flow through deep transand is about 120 miles in length, its breadth varying from 15 to 60 verse valleys, forming openings through the eastern slope into the miles. Its surface, to the eye a perfect flat, varies in elevation from low country at its base, and thence into the ocean ; just as the waters 16,000 feet along its outer edges, on the south-west and north-east, to accumulated in the two great Indian rivers are discharged by openings about 15,000 feet in its more central parts, where it is cut through by in the Himalayan or southern slope of the Asiatic table-land, through the river Sutlej, which flows at the bottom of a stupendous ravine, the plains of Hindostan, into the ocean. formed out of the alluvial matter of which the plain is composed to a The African table-land, as a whole, may be described as a succession depth of 2000 or 3000 feet, and at its west end even more.” But of extensive undulating plains (like the corrugations and so-called plains the table-land itself, it must be remembered, is a mountain-mass. of Tibet, already mentioned), but dipping very gradually towards the “ The so-called plains” of Tibet, Dr. Hooker remarks,“ are the flat west and north-west, and intersected by numerous streams, which, floors of the valleys, and the terraces on the margins of the rivers, after a short course over the surface of the plateau, fall abruptly into which all flow between stupendous mountains,” either those of the the deep-cut fissures or valleys just noticed, in which they soon reach northern and southern slopes or faces, or of the corrugations already a depression of 3000 to 4000 feet below the general level of the tablementioned.

land. In addition to the irregularities produced by these valleys, the In South America, contrasting with the lofty plains of Quito, of uniformity of the surface is broken by loftier mountain-masses, which Santa Fé de Bogota, &c., are the llanos and the plains of the Amazon ; in some parts of Abyssinia attain an absolute elevation of from 11,000 while in North America, the interminable prairies and the low swamps to 15,000 feet. The eastern edge of the plateau itself has been clearly round New Orleans form a striking contrast with the Rocky Mountains traced as far as the ninth parallel of north latitude, to which distance and the elevated plains of Mexico.

it forms the water-parting between the basins of the rivers Nile and Of Africa co..paratively little is known; but if the plains of Lower Hawash. “How much further it extends southward,” Dr. Beke Egypt and part oi the Sahara are very low, there are high plains in remarks, "our present knowledge scarcely enables us absolutely to some of the mountainous regions.

determine; but we may safely regard it as reaching beyond the The great plateau or table-land of eastern Africa, according to Dr. equator." The snowy mountains observed by Captain Short, and those Leke, to whose continuation southward of Dr. Rüppell's investigations discovered by the missionaries Krapf and Rebmann south of the we mainly owe our present knowledge of it, begins to the south of the equator, appear to be connected with the broad mountain range of country of Taka, in about 15° of north latitude, where the anticlinal eastern Africa, of which the Abyssinian table-land forms the northern axis between the Nile and the Red Sea rises rapidly till it attains an portion. These are the “ Mountains of the Moon" of the natives and elevation of 7000 or 8000 feet above the level of the ocean. At Halai, of the ancient geographer Ptolemy, which Dr. Beke has proved to be at the summit of Mount Taranta, not more than eighteen geographical thus a meridional and not an east and west chain, in which are the miles from Zulla (the ancient Adule, recently, 1860, taken possession of sources of the Nile, and which form the eastern face of the tableby the French government), near Massowah, the edge of the table-land land in its southern extension. The continuation of this range was has an absolute elevation of 8625 feet, which gives a rise of 1 in 12:7, crossed as far south as 7° 30' south latitude by the recent travellers, equal to an angle of 4° 30' with the horizon, to the eastern slope of the Captains Burton and Speke. Detailed information on the whole of table-land (or, as it may be more correctly called, in Dr. Beke's opinion, this subject, with maps and sections of the country, will be found broad mountain-chain of Abyssinia). The western counter-slope in Dr. Beke's work entitled “The Sources of the Nile, London, 1860; towards the interior of the continent has a fall of 1 in 343-7 only, from which, except as otherwise indicated, and with slight variations giving an inclination of 10'; consequently, on a direct line from east to of description, the preceding view of the African table-land has been west along the fifteenth parallel of north-latitude, the eastern slope of derived. the Abyssinian mountain-chain (or table-land) towards the sea is, to Plains differ not only in their elevation, but in the horizontality of corresponding with the courses of the principal rivers from south-east circumstances, together with their geographical position, influence their to north-west, the eastern slope has a rise of 1 in 38.83, equal to an climate and productions, and give to the most considerable among angle of 1° 41', and the counter-slope of 1 in 460, or 7' 30", giving the them a particular character and physiognomy. It may be remarked proportion of 11.8 to 1. In making this estimate, however, the rise of that the rocky and sandy plains belong almost exclusively to the hot the eastern slope is not taken from the level of the sea, but from that and temperate regions of the old world. The plains of America are of the river Hawash, which is the recipient of the waters of the eastern generally characterised by their gramineous covering or their vast slope as the Nile is of the western, and has itself an absolute elevation forests; the Asiatic steppes by a twofold appearance, being in some of 2200 feet, at a point distant from the sea about 200 miles. This, parts studded with low saline plants, and in others, as in southern again, gives a fall of about 1 in 550, equal to an angle of 6' 15", for Russia, Siberia, and Turkistan, covered with plants of the families of the eastward dip of the comparatively low-level country between the the Compositæ and Leguminosce ; while, the greater part of the European Hawash and the Indian ocean. “ As regards the counter-slope of the plains are richly cultivated. Abessinian (Abyssinian) chain,” Dr. Beke says, “it would seem that the We say such are the general characteristics, for there are plains of fall of the land towards the Nile in the western portion of it is con- similar character and physiognomy in very different and widely separated siderably greater than it is in the eastern; so that the surface of the table- regions of the world. The high land of the Campos Parexis, for lind, or broad suminit of the mountain chain, approaches more nearly instance, in South America, is very similar in physiognomy to the to a level than if the slope were the same throughout. It is certain, desert of Gobi in Asia. The Desiertos, near Coquimbo, are of the same however, that the table-land nowhere forms an absolute level, and that character as the Sahara. The Puszta of Hungary resemble the savannas the general dip westward commences from its extreme eastern limit." of the New World; and the pampas of Cordova are not unlike some

This table-land, as the same geographer has shown, may, in the most of the Siberian steppes.