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from it and will adopt very quickly that velocity which the time the great relative velocity could remain constant the adjacent parts of the cloud possess.

such a resistance must have iaken place that could develor It is interesting to compare this process with a similar one, the heat necessary for the glowing of the body? We are hoc which takes place in a well-known way in the appear. going to decide this question by comparing the resi-sing on ance of shooting stars or fireballs. In this case a com of the star to that of a meteor in the upper strala of oars pact body enters with a certain velocity into a formation inospbere. of very thin matter (the upper stra'a of the atmosphere), is Let us assume, quite generally, that the motion of the six: heated and partly va pourized, and a luminous tail, which is a straight line is given by the equation clearly visible for a long time after the sudden appearance of

do The meteor, marks the path which the latter has taken. The

= - lv, ...... ....1 detached particles have quickly lost their relative velocities against the air, for they apparently do not partake of the move- | (1) where v is the velocity, na positive number > I and a acr ment of the meteor.

stant, which is directly proportional to the surface of the glates If we consider spectroscopically the star on its commence body and the density of the medium and inversely proportijn ment to become bright by resisiance, two superposed spectra to the mass of the body. We compare equation (1) with will openly reveal themselves, one in general continuous and equation for the motion of a meteor provided with absorption bands in consequence of the heaping

d up of the glowing gases, and the other in the main consisting of bright lines. Both spectra, according to the relative motion in the line of sight, will appear pressed up against one

in which the time t is reserred to another unit selected for

purpose. If we suppose vi' = uv; t = vl; 1 = a -1. 12 another. Thus altogether an appearance is found very similar

latter equation beco.nes identical with (1), thai is the moveut to that observed in Nova Aurigæ, and they will agree entirely

of the star corresponds point to point with the motion or if one assumes that also those parts of the cloud nearest the

melcor, if the latter equations are satisfied. Representing and body have sustained physical periurbations by a direct frictional

m, 0, r, s, m, O', 1,8, as masses, surfaces, radii, and retssa warming of the detached particles, &c. This assumption

of the star and meteor, and D and D' the density of the cust! seems to me to contain by no means a difficulty considering our lack of knowledge wiih respect to the properties of this

clouds and the upper strata of the atmosphere in questica, **

have :cloud matier. Whether ihis is at all necessary I am unable to

DOm'

DOE say on the ground of the publications at hand.

a = The investigation is important to decide whether, on the

D'O'm

4*-1 - D'U'. lines laid out, we can obiain a plausible explanation of the

or also great relative velocities shown by the two spectra. When the body approaches the cloud the latter will evidently lengthen

ro i'self in the direction of the former. This lengthening will

If we put r = k times the sun's radius ( = 700 million mets grow with the mutual approach, just as the relative velocity of

and r = r' metres, and further corre-ponding to the observati: The single parts of the cloud will grow towards the body.

of the new star v = 30 (unit of velocity of Earth in its orbit) Without certain suppositions on the structure of cloud matter

( = 100 days and v' = 2 which corresponds to a relative; it is difficult to conceive of the processes of movement which

| quickly.moving meteor and finally n = 2, we have :take place, so we must content ourselves with contemplating the one or the other case, which admits of a closer invest

_ 15. D8'. quel igation.

k U'700 millions If, for instance, we suppose that the single particles of the

and t' =0%. 183f; f = is cloud follow for the main part the effect of the body, they will describe conic-sections—that is, hyperbolas round the centre of

| Thus the movement of the star takes place proportionally in 13 the latter as forces. Their greatest relative velocity decreases quickly with the distance of the body, so that the surroundings

days, just as that of the meteor in 5*185 seconds if we suppress of the latter will be filled with particles moving with very ful. As we are free to assume , small, we can obtair : different velocities. One can easily see that no very extra ordinary assumptions are necessary to suppose very great velo.

very small fraction of a second, and since within a hundred cities for these particles that pass near the surface of the body, part of a second the movement in the highest regions of oatvelocities amounting to those stated in the case of Nova Aurigæ,

mosphere shows no longer a perceptible decrease of vele, even if they are at the outset very small. It follows from the

such a decrease will not enter in the case of the star. We har above that the spectral-lines of the particles which are moving

evidently to deal here with the same appearance which partfrom the body with such different velocities must be very much

out that small heavy objects possess a lar greater resistance' enlarged, and that to explain the different brightenings of the

air than large ones, and that with large meteors (fireballs. single parts of the lines as probably intensity maxima does not

air resistance, as it has been proved, influences the elenco's. jaise the least difficulty, but is a necessary accompanying phe

the orbit far less than is the case with small meteors. nomenon. This point seems to me to be important, for it can

We have still to show that in spite of the small decreas not be deduced from the hypothesis of two compact masses

movement, enough energy of movement is changed into he: passing close by one another, and must here lead to the rather

order to bring the star into a surface-glowing condition, and s.' improbable assumption of several moving bodies.

a condition has by all means taken place in the Nova in As long as the body remains in this, so to speak, atmospheric

must therefore calcuiate the quantities of beat Q and O' . formation, the appearances above mentioned must always be

is radiated in one second of time, and from a unit of surface called forih anew, whence it follows that the peculiarities of the

both bodies. If we call P and P' the losses in acting poss spectrum conditioned by the whole state of things, not consider

during the times ( and t', Voand 70' the velocities before", ing smaller perturbations, must on the whole remain constant entrance into the resisting media, we have :for some time, a point which in the above hypothesis is at first

pi not by any means clear. In a similar manner it will not be astonishing if ihe star during that time changes its brightness less strongly, while after its exit from the cloud this brightness will

and P= m (9,2 - 72); P=m (7"-) decrease rather rapidly. This too agrees with the light-curve in and taking into consideration the above equations : the case of the Nova. Finally, even the periodical fluctuations

Q_D (0) »+2 of the magnitude can be explained quite naturally. We call to

Qulu mind bere the well-known fact conlirmed lately by the photographs of Max Wolf, that similar occurrences appear in shooting with the above numbers 2,= 15; n will be = 2 stars, which may, indeed, be explained with difficulty.

We must, however, in any case assume that the star entered the cosmical cloud in question about the beginning of December and lest it not long before the beginning of March. Now the so that we can assume that the density of the cosmic med.. question is urged upon us How was it possible that for such a long compared to these already very thin air strata, in which evide

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the glowing of the meteor occurs, is not very dense, and that

Tezi's! 20 40' 60 80 100 one yet gets the necessary quantity of heat.

- - -

-- - ---It may be remarked that we can vary all these numbers | F = 4' 10.207 14:393 | 24.882 32'111 I 37.988 43'071 within very wide limits without fearing any contradiction, so

8! 5'224 7.302 | 12-554 16-182 | 19:135 21689 that we may conclude, therefore, that no difficulty in the sug

3614 49878 494 10'930 12'913 14'630 gested hypothesis arises from this point of view.

2.852' 3.866! 6505 8343' 9.853 11156 I have now to deduce the formulæ I have mentioned above,

2-429 3'226 5 345 6.838 8059 9:118 and it will be seen that these are very interesting.

2'178

2.827 4.603 5.806 6'902 7.802 If we lake n as the sum of two masses revolving round each!

2'027 2'569 4'343 5 204

6.902 other in a conic section, V ihe velocity, and retaining for the rest

1941 2'400' 3.753 4740 5555 6*265 the customary nomenclature, we have for the parabola

I'900 2'293 3.510 4411 51585810

1092 V2 = kau

2'234 3 345 4:181 4.877 5 486 ?; r = w ; cosa /20'

1911 2211 1 3 '240 4'029 4.688, 5'266
1'953 2'2 3:1873 941 4574 5131

2'017 22
kay ul.
0+3/lan3 1/. =

3179 3911
lan

4.528 5.072 12 V 2

2:101
2323 i

3-217 3.936 4.547 | 5'086

2'208 Whence it follows without further difficulty :

2-341 2'552 3438 4'170

5*351

2-510 2'729! 3044 4.404 5 056 5 635 4k-sin /v11--13 sin-1), v1

2 728

2'968 3 944 4754 5451 6'070

3:307 / 4 390 5.286 6.055 6-739 One takes c as the velocity of the earth in its orbit with the

3 477 ! 3830 5 108 6 152 7'048 7.843 radius R and puts the sun's mass and the mass of the earth=1, 84 4'308 4.802 0'480 7.824 8:972 9.991 so that k=c'R. If we consider further that the expression

88 6-991 7938 '10 960 13 320 15-321 17.091 sin", v [1 – 2/3 sin/2 v] can attain the maximum value »? it follows that

For very large values of e the minimum of X occurs if

sin F = 12/3,

and the minimum value of X becomes 4 12

Min X = 33:4 = 1.612 de.....(6) or if e be given in solar days

V 2 But one practically commits no error is one employs (6) also for the values of e nearly equal to 1, as is evident from the following

computation of the minima values taken from the above table, To apply this to the Nova we must remember that > 15 | and calculated according to formula (6). because the orbital velocity may be greater than that in the line

Direct.

Formula. of sight. Besides, more than two months have passed since the

15 supposed grazing of the bodies took place, which time must

19 coincide closely with that of perihelion, up to the time that we bave still spectrum ob ervations in hand. Thus t is much

3'2

32 greater than 60. Formula (4)

3:9

45 M-14779 X sun's mass gives thus a limit which supposes masses far too small. In

One ubiains :reality we might perhaps assume double this without challenging contradiction.

u> 001040

) ve.l. ...(0) The coasideration of a hyperbolic movement takes a similar Though less simple forın.

For the above assumptions11v represents the velocity at an infinitely large distance, we have V? - V;* = 2kļu,

we find and according to the Theoria MotusLC - cos F

which formula holds good for values of e, which do not quite
equal i. In order to include also the parabola we suppose

V2 - V13/2
e tan F - log tan (45° + 1/2 F) = *
ri_kvu.[

u > 15000 Vel.

vel. V:
V )

......(7a)

... from which it is found at once that -

Thus in this case we result in extremely large masses, which are not very probable, or we must assume that = very nearly 1.

« .-0009123()% ......(4)

10

2

2

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Even for = 0-9, according to the above formula, u > 1 200 de, Cust ) clan t - 103 lan (45° + 1/2 F) and we may consider the above-given assertion as justified. It

has already been remarked that this suggested inequality proves The expression for X, if one allows F to vary from 0-90°, first

irst only that u is very much greater than the right side (of the

on decreases, reaches a minimum, and then increases to infinity.

inunity. equation). minimurn value can easily be determined for then

It is easy to find a higher limit for u is does not differ much 3 e sin 2F

setan F - log tan (45° + 1/2 F)] must be = 1. 418 - cus 1)?!

from unity.

V2 - V._ This equation can be easily solved for special values ofe. If we put --"; = v, we obtain cos F = ve, and according For the theoretical calculation which is requisite, I have em 1 ployed another proceeding, as I have already computed the

| to formula (5) : serial values of X for a special value of e, as the following table (1 - 113?(V3ct shows :

(1 + v) (c) R ev tan F - v loylan (45° +1/2r;

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Given t, e, and v, we can calculate the right-hand side. But An easy calculation yields now we seek, however, the maximum value of y=ev lan F – v log tan (45° + 1/2F)=sin F - v log tan (45° + 1/2F) |

[(1 + e*) cas F 24

OF esin F - cos F loglan (45° + 1/2F) ." hy determining e as function of v. It is

+ esin F log tan( 45° +12F; v əfvI - ve”) cos F) de

It is quite evident that the quantities in brackets always reme enī - vše?

positive, for it is Thus y increases so long as e < , and decrease; continu log tan (45° + 1/2 F)=2 tan F+tan3 1/2 F + ... > 2 tan 1,'2F,

and in consequence of it the quantity in brackets >e - 1)*cos F. ally for e > ,: The maximum for y takes place when e? =-,

Thus, is negative, and y decreases as F increases. From and is

this it follows that y>I, and the relation r>V., is the resalt.

If we apply this formula to Nova Aurigæ, we obtain for Thus we have

= 0'5 VV- V= 108 miles, V. = 60 = =;. (8)

0:6

96

72 TL + Ni - v

86 Vi - v - v loga

84

108 o and 1 = 60 days,

In the vicinity of perihelion the velocity has been under every - 3,2

condition greater than 120 miles, and we shall therefore obtain values of v that are considerably too small, by supposing p> t x 85 miles. One day before or alter perihelion it is there.

fore certain that r>7'3 million miles. For the above example y = 0:9 results u > 2800 as considerably It will therefore hardly be possible to assume that any notice

able influence of the supposed two bodies can have lasted longer larger masses than sormerly.

than a few hours. I have now further to prove that a very close proximity of the Since the above article was written Nova Auriga has by its two bodies can have only taken place for a very short space of reappearance attracted considerable attention, and especially by time. To do this we use the following relations.

the observation as made by Prof. Barnard. With regard to this We find above for the parabola :

reappearance one must necessarily se an evident confirmation

of the critical part of my article. Nor bas my hypothesis been ? ; x = sin }v(1 – 2/3 sin’ 1/2v).

contradicted in any way, for it is evident in itsell that the It follows, therefore, that

supposed formations of the nebulous or dusty matter are mare copious in certain parts of space, and one may have diffețent ideas of the distribution of density of these formations.

To the observation made by Prof. Barnard (Astr. Nace,

3114) I wish to add the following remarks. I had formed an 2.r

idea of the whole process wbich caused the outburst of the Nora, Thus we have

which idea is as perfectly represented in Prof. Barnard's drawing, kindly communicated to me by Prof. Kreutz, as I could expect. During the appearance of the Nova in i be winter nothing similar

was seen so far as I know. It does not follow from this, For the hyperbola we have

therefore, that it did not exist, and it would also have been 2ku

possible to have expected information from the photographs ar V? - V .

has often occurred before. I applied on this account to Dr. and, according to formula (5)

Wolf, in Heidelberg, and asked him whether he bad photographs of the region of the Nova at that time, and whether,

perhaps, any nebulous object was to be seen on them ; but, un12

fortunately, Dr. Wolf did not possess such photographs. Therefore,

11 remains doubtful, I am sorry to say, whether so delicate an objec: r = VV: - V. x.

would have been visible on the plates. W. J. LOCKYER.

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HINTS FOR COLLECTORS OF MOLLUSKS.! AFTER the collector has brought hoine the spoils of his - excursion there is still a good dcal to be done before the wet and dirty shells, covered with parasitic growths or in. habited either by the original mollusk or soine hermit crab, will be ready to be placed in the cabinet. Some of them, if living, may find a temporary place in an aquarium for the study of their habits, but, for the most part, the collector will wish to prepare his specimens either for anatomical use in the future or as dry specimens for his cabinet. The preparation of mollusks for anatomical purposes has been described in a special chapter of these instructions. For ordinary rough work nothing is better than clean 90 per cent, alcohol diluted with a proper proportion of water. If the specimens are large they should be first put iato a jar kept for that special purpose, in which the alcohol is com paratively weak, having, say, 50 per cent, of water added to it. After the immersion of specimens in this jar for several days the Auids will have been extracted by the alcohol, and a specimen can then be removed, washed clean of mucus and dirt, which will almost always be found about the aperture of a spiral shell, and

' Reprinted from “ Instructions for Collecting Mollusks, and (ther Vidal Hints for the Conchologist," by Wilham H. Dall; issued by the Smithsonia Institution as Part G of Bulletin of the U.S. National Museum, No. 3x

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ced in its own proper jar of 90 per cent. alcohol diluted in sketched in the living state. Some of the older naturalists bad proportion of 30 per cent. with pure water. Specimens to be a way of skinning slugs, inflating and drying the empty skins for pared for the cabinet require the removal of the soft parts if preservation in their collections, much as entomologists somey are still present, the cleaning off of parasitic or incrusting times treat caterpillars ; but this ingenious device has nothing wihs, and, in the case of bivalves, securing the valves in a to recommend it to a scientific collector, even if he has the Ivenient position for the cabinet. The different classes of dexterity to practise it. The internal shell of such slugs as :lls may be treated under several heads.

Limax may be represenied in the collection if desired, but, in

any case, specimens should be carefully preserved in spirits. Land and Fresh-Water Shells.

The bivalve shells, such as Unio, if taken alive, may be left Land and fresh-water shells are much more easy to deal with in the sun for a short time, when they will usually open, and, n marine shells. In the case of spiral shells, such as Limnæa. the muscle connecting the two valves being cut, the valves may Inorbis, Paludina, &c., the shell may first be washed clean

be cleaned. It is desirable for cabinet purposes to preserve the mud or comfervoid growth, which may be conveniently done

two valves in their natural position, attached to each other by in the assist ance of an old tooth or nail brush. In the case of

the ligament which holds them together in life. This ligament se forms the easiest way to remove the soft parts is to place dries to a very brittle, borny substance. Consequently the shells : shell for twenty-four hours in weak alcohol, after which those must be placed in position when fresh in order to make a success rts can readily be removed ; brat in any case where the expense of the operation. After cleaning away the animal matter and

alcohol is an object to be avoided, it will be sufficient to thoroughly washing the interior of the shell, it is a good plan to ice them in a small tin kettle, or other receptacle suitable for note the locality with a soft lead-pencil upon the shell itself. e purpose, and cover them with cold water, which should then Then bring the two valves together in their natural position and slowly brought to the boiling point. As soon as it has reached tie them in that position with a piece of tape or sostiwine, which e boiling point it may be removed from the fire. The shells should be allowed to remain until the ligament is thoroughly ould not be put into water already boiling, as it frequently dry. Specimens prepared in this way are more valuable for acks delicate shells, and the sudden change of temperature exchange and more attractive to the eye than those with which jures their polish and general appearance.

less care has been taken. It is always desirable, however, to For removing the soft parts from spiral shells the collector have some specimens with separated valves of every bivalve Hll usually hnd a crooked pin sufficient. For this purpose one species in the cabinet, in order that the characteristics of the those long steel pins used by ladies as hat pins is convenient. J interior may be easily examined. y heating the pointed end in the fame of a candle or alcohol Fresh-water bivalves are usually covered with a thin and highly mp the temper can be taken out of the steel, so that it can be polished, often very elegant, greenish or brownish epidermis. adily bent into any shape desired. The proper form for

| Sometimes the shell is so thin that, in drying, the contracting aching the retracted parts in a spiral shell will of course be a | epidermis splits and cracks the shelly portion so that it becomes iral. With a small pair of plyers, different forms can be ex worthless for the cabinet. This olten happens with marine rimented with, and those which are most satisfactory decided mussels, but it is almost characteristic of the thin fresh-water on. After the right form has been obtained, by heating the

Unionida. Various methods have been adopted to prevent this n again and plunging it suddenly into cold water, the temper

unfortunate result. Some collectors have varnished their shells the steel will be measurably restored and the instrument immediately after they were obtained. Others have used sweet ady for use. Similar pins in their ordinary condition are con

oil or other oils in the hope of keeping the epidermis in a soft nient for cleaning out sand or parasites from the recesses of

condition. These applications are all objectionable for one ulptured shells, and for other purposes. The attachment of a reason or another, as the first endeavour of the collector who stropod to its shell is at the central axis or pillar of the shell, desires to make a really scientific collection should be to keep ually from half a turn to a turn and a quarter behind the aper

his specimens as nearly as possible in a perfectly natural conre. By applying the pressure of the extractor carefully in this dition. The most satisfactory substance for application to the cinity the attachment will give way and the extractor may be shells in question is probably ordinary vaseline, which should be ithdrawn, bringing with it the soft portions of the animal. In applied in very small quantities, so that the specimen will have rge and heavy shells, in which the muscular attachments are

no greasy feeling and will absorb the vaseline sufficiently not to rong and deep-seated, and it is desired to obtain a good hold

become sticky to the touch. Glycerine, which hias been recomthe animal in order to extract it from the shell ordinary steel

mended by several collectors, like oil, leaves the sursace sticky h-hooks may be used. These may be softened by heat,

and offensive to the touch, besides rendering it liable to catch raightened out, and twisted into a spiral of the proper form,

everything in the way of dust with which it may come in id retempered. Then they can be securely fastened to

contact. wall wooden handles by the shank of the hook. In this way

Very small gastropod shells need not have the soft parts ree barb or the hook will assist in retaining the soft parts on the moved. If they are put into a vial of alcohol for twenty-four tractor when it is withdrawn from the shell. Several German

hours, then taken out and allowed to dry, the soft parts will ms advertise sets of implements for cleaning, cooking, and

become desiccated without any offensive odour, and ihey may tracting the animals from shells of mollusks, but it would seem

be placed in the cabinet without further preparation. It may be the writer that any person of ordinary intelligence and some

noted, however, that is the cabinet contains many such shells, tle mechanical ingenuity, such as all naturalists are expected

care should be taken to guard against the access of mice and vermin, possess, should be able to provide himself with the necessary

which are apt to attack them in the absence of something more paralus without purchasing expensive paraphernalia of this

attractive in the way of food. For those shells which possess d. Shells which have no operculum require merely to be

an operculum, after the operculum has been dried and the shell aned after the animal has been removed, and in the case of

cleaned and ready for the cabinet, it is customary to insert a d and fresh-water shells this is usually a very simple matter. |

little wad of raw cotton, rolled so as to fit the aperture snugly, ells which possess an operculum should retain it in the the outer surface of it being touched with a drop of mucilage. vinet, as it is often of great value in determining the relations The operculum can then be laid upon this in its natural position The species, since the operculum is a characteristic feature in

and the mucilage and cotton will retain it so without making it economy of the animal. It should be detached from the

difficult to remove for an examination of the shell if desired at any ly of the animal alter the latter has been extracted from the

time. For the preservation of eggs of mollusks when they have a

time. For the preservatio 11, carefully washed and cleaned, and if flat and horny may horny or calcareous shell, small glass tubes securely corked are the dried between two pieces of blotting paper, under a weight. I best receptacles. Most of these eggs are so small that they may be is will prevent it from becoming contorted in the process of preserved in a dry state or in alcohol without trouble, but the ing. For removing the thick incrustation of lime and per- eggs of some of the tropical land snails are so large that it will le of iron which frequently forms upon fresh-water shells, a be necessary to drill a small hole and extract the fluid contents

tools resembling engraver's tools or the little chisels in use as if they were bird's eggs in order 10 preserve them. Such lentists for excavating teeth are very convenient. A suitable eggs are the best preserved in alcohol. , however, can easily be made by sostening and grinding in an old file to a triangular point. A little experience will

Marine Shells. ble the collector to become expert in scaling off the objection The preparation of marine shells for the cabinet does not matter without injury to the surface of the shell.

essentially differ from that required for land or fresh-water aked slugs should be preserved in alcohol, after being shells, except that in the marine shells the muscular system is often much more strongly developed and the creatures them- fish, like Pholas, frequently have accessory pieces, which selves much larger than the fresh-water forms, and the manipu- liable to be lost when the soft parts are removed unless ce lation is therefore somewhat more difficult. The marine forms taken to avoid it. Other bivalves have the internal ligzne are also more apt to be incrusted with foreign bodies, bored by reinforced by a shelly plate, which is called the Ossican predatory sponges, like Cliona, or even by other mollusks, or This is very easily detached and lost, and, being an obic perforated by certain annelids which have the power to dis great interest, special pains should be taken to preserve solve the lime of which the shell is composed, and in this way even if it should become detached. secure a retreat for themselves.

Shells which do not contain the living animal are frequently occupied by hermit crabs or by tubicolous annelids. The latter fill up the larger part of the spire with consolidated sand or

JAPANESE CAMPHOR. mud, in the centre of which they have their burrow. The THE United States Consul at Osakaigives in a recent te hermit crabs do not add anything to the shells which they the following particulars, reprinted from the Norene occupy, but, on the contrary, by their constant motion are apt number of the Board of Trade Journal, respecting the Japete to wear away the axis or pillar of the shell, so that often a camphor trade: specimen of this sort may be very fairly preserved and yet on The camphor tree, from which the resinous gum is distrs the pillar show characters entirely different from those which is a species of the laurel, and is found in the provinces of Tx one would disco, er in a specimen which had never been occu Hiuga, and Satsuma, in the south of Japan. Large grond: pied by a crab. A shell which the crab has selected for its the trees are owned by the Japanese Government, the va home is often taken possession of, as far as the outside is con being very desirable for shipbuilding. The districts in cerned, by a hydractinia, a sort of polype, which produces a the camphor tree is found are mountainous and situated far horny or chitinous covering which is very difficult to remove the sea. No reliable information can be obtained as to the from the shell to which it is attached. As the hydractinia grows of producing the gum before being transported in junks to Hzę it finally covers the whole shell, to some extent assumes its The peasants who engage in distilling the roots and brands form, and then, if the creature has not attained its full growth, the trees are said to be poor, and employ the rudest machine this is apt to take place around the edges of the aperture, which The market value of crude camphor gum and of oil of cae: are continued by a sort of leathery prolongation which assumes per picul (133} lbs.) during the past year was as followin a rough way the form of a shell. The crab, when he grows Drained, 38.25 dols. : wet, 37'00 dols. ; old dry, 43°50 dou too large for the shell in which he has ensconced himself, is average, 36'50 dols. ; camphor oil, 5'25 dols. usually obliged to abandon it and find a larger one, which is The highest and lowest prices during the same period wert always a difficult and more or less dangerous operation ; but if follows :-Highest, 40'00 dols. ; lowest, 33.00 dols. his shell is overgrown by the polype referred to, it often happens Camphor gum is exported in tubs measuring about 6 ay that the polype and the crab grow at about an equal rate, so feet ; oil in kerosene tins and cases. The grades are from that the latter finds himself protected and does not have to dry down to new wet, and the various grades depend op 1 make a change. It is supposed tbat the polype profits to some quantity of adulteration. In oil there are two grades-wbikes extent by the microscopic animals attracted by the food or ex. brown. crement of the crab, so that this joint housekeeping is mutually Adulteration is practised for the most part by adding a beneficial, and, for such cases, since the word parasite would and oil just as far as the buyer will tolerate. In some * not be strictly accurate, the word commensal has been adopted. 20 lbs. of water will run out of a tub in twelve hours. 11 These modified shells often assume very singular shapes. "The unadulterated article, known as the good old dry, cao su polype is able in the course of time to entirely dissolve the times be bought. The only system of tests in determining original calcareous shell upon which its growth began, so that of the different qualities is by burning and by absolute spirit if the spire be cut through it would be found throughout of a percentage of pure camphor which ihe crude yields when resa horny or chitinous nature. Some of the older naturalists were varies according to the quality of the crude. The average deceived by forms of this sort and applied names to them, sup: centage of gum produced from the wood as compared with posing that they were really molluscan shells of a very peculiar original weight of the wood cannot be accurately asceren sort.

here, the only foreigner known to have visited the camphor a In removing the animal matter from the shell of large gas. tricts having declined to furnish any information on the sche tropods it will often require a good deal of time and care to get The total exports of camphor from Hiogo during 1801 out all the animal matter from the spire, but it is well worth catties of 14 lbs. each amounted to 3,850,400 catties consiga while to take the trouble, as the presence of such matter forms a to the following destinations : Europe (countries not speak constant attraction for museum pests of all descriptions. A 1,777,300 carties ; London, 335,600 catties; Gers medium-sized syringe is convenient for washing out the spire of 209,200 catties; United States, 1,277,000 catties; C such shells. The ordinary marine gastropods may be treated in 51,900 catties ; France, 199,400 catties. a general way like the fresh-water gastropods. There are, As regards the manufacture of camphor the following: however, abnormal forms, especially among tropical species, i ticulars are extracted from a report by the United States ( which require particular attention. Some species become at Nagasaki. affixed to corals and overgrown by them, retaining only a small Camphor is found alike on high elevations and in the fall aperture through which the sea water can reach the prisoner. | and lowlands. It is a hardy, vigorous, long-lived tree Such specimens are best exhibited by retaining a part of the flourishes in all situations. coral and cutting the rest away, showing at once the mode of Many of these trees attain an enormous size. There occurrence and the form of the covered shell. Borers are number in the vicinity of Nagasaki which measure 10 20 always more difficult to handle and prepare for the cabinet in diameter. The ancient temple of Osuwa, at Nagasa than other mollusks. They are usually more or less modified situated in a magnificent grove of many hundred greedy for their peculiar mode of life, and frequently rely upon their camphor trees, which are of great age and size, and s burrow as a protection, so that the shell is reduced, relatively beautiful and vigorous. It is stated that there are trees to the animal, to a very small size. Most of these forms are places in Kiu Shiu measuring as much as 20 ft. in de best kept in alcohol. The hard parts may properly be repre The body or trunk of the tree usually runs up 20 and 30fPP sented in the cabinet by other specimens. Some of the bivalves, limbs, then branching out in all directions, forming a such as the American " soft clam," possess very long siphons, proportioned, beautiful tree, ever green and very orname covered with a horny epidermis, and it becomes a question as The leaf is small, elliptical in shape, slightly serrated, to whether an attempt should be made to preserve this epider a vivid dark-green colour all the year round, except for !! mis in the cabinet or not. The writer has seen very nicely or two in the early spring, when the young leaves prepared specimens in which the fleshy portions had all been delicate, tender green. The seeds or berries grow in D taken out and replaced by cotton, so that the epidermis of the and resemble black currants in size and appearance. E slphon retained its original position and form ; but such speci. | is used for many purposes, its fine grain rendering it mens are always very delicate, easily broken, and liable to valuable for cabinet-work, while it is used also for shiple attack by insects, so that it would seem hardly worth while to The roots make excellent knees for ships. go to the trouble, when specimens may be preserved complete In the manufacture of camphor the tree is Dee in alcohol showing all the features referred to. Boring shell: destroyed, but, by a stringent law of the land, anothers

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