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theory of Weismannism minus natural selection. In the second place, we believe that Weismann means permutations, though he uses the term combinations. After a football team has been selected, the men can be arranged in 11 different ways. The arrangements would virtually constitute new teams, and newspapers would speak of them as strong and weak combinations. The combinations of the Ahnenplasmas can be assumed to be of a similar kind. The arrangement almost certainly counts for something. Nevertheless, Prof. Hartog's contention-that the elimination of Ahnenplasmas in the shuffling process would lead to ever-increasing simplicity-demands serious consideration, for duplication lessens the possible number of permutations and combinations. I would point out that we may conceive that the Ahnenplasmas were, in asexual unicellular organisms, either all the same, all different, or in intermediate conditions. In any one of these cases we must assume that m, the number of individuals, was much greater than #, the number of Ahnenplasmas present in every individual. With the evolution of sexuality (all the individuals being different) we should get combinations of, at least, m Ahnenplasmas taken n at a time. Different permutations of the same combination would be, of course, possible, giving rise to other combinations, using the word in the general sense. We must suppose that natural selection operated upon the variations produced by these first combinations. Natural selection had operated upon the unisexual ancestors of these sexual forms. We can at least conceive that development would follow one of two courses. Along the first, combinations in which more than one unit of a kind appeared would, if possible, be prevented. Such might arise, but under the operation of natural selection they would not be allowed to perpetuate themselves. Along the second, such combinations might arise and be perpetuated. In either case, it must be assumed that the combinations which survived were such as were best adapted to the varied combinations of external conditions. This may be made clearer by an illustration. In Rugby football, combinations of 15 in which 8 or 9 of the men-the forwards are all the same would be strong, whereas, if all were different, they would be weak. In Association football, strong combinations could only be made up by selecting different types of players for the different places. I am inclined to believe that both cases are followed by Nature. The one which I have illustrated with reference to Rugby football cannot, however, have been generally followed. It is an adaptation for which the organism has ultimately to pay dearly, and is as dangerous to the development of the phylum, as we may suppose parthenogenesis to be to the species. Taking the case of plants, I would say that the one course may have been followed along the line of development of the main archegoniate series, the other in the development of such divergent groups as the Ustilaginea and Gastromycetes. The argument of Prof. Hartog, therefore, while of no avail as directed against Weismannism, is of use in so far as it enables us to better understand divergence. I am inclined to think that it may serve also to explain the remarkable persistence of such forms as Nautilus. It suggests, too, an explanation of the disadvantage of breeding “in and-in." Finally, I would remind Prof. Hartog that neither of the disciples of Weismann apparently believes in the non-variability of the Ahnenplasmas. If their beliefs have a substantial foundation, it follows that the number of possible combinations becomes absolutely unthinkable.

I shall be much obliged to Prof. Hartog if he can inform me of any theory of heredity whose foundations are not "more or less mythical." There are, no doubt, many difficulties in Weismannism, before one of which, the theory, having served its time, may come to the ground. I do not think that Prof. Hartog's is one of them. A. H. TROW.

Penarth, Cardiff, December 10.

Destruction of Immature Sea Fish. IN your number of November 19 (p. 49) you review the Ninth Annual Report of the Scotch Fishery Board. I have not seen the Report, but assume that your reviewer's statements as to its contents are correct. My object in writing is to draw attention to the opinions attributed to Dr. T. Wemyss Fulton as to the destruction of young fish by shrimpers. I may say at once that I am one of the "very many" to whom the "results" are "surprising" as your reviewer remarks. I am an old shrimp-trawler in the Dee and along the Flintshire coast, and I have no hesitation in saying that, as regards the Dee and, I believe, the

Mersey and the Lancashire coast as far north as the Ribble, the destruction of young fish is absurdly under-estimated, whether I judge by my own experience or by that of Mr. R. L. Ascroft, of Lytham, with whom I have been in correspondence on the subject since 1889. This gentleman, however, informs me that Dr. Fulton's information was obtained from Morecambe Bay, where smaller trawls are used, and the boats drift with the tide instead of sailing. Dr. Fulton has been informed that in the Solway Firth a single boat in one year captures over 110,000 immature plaice. If the word " year" is not a mistake for "week," either the statement is immensely under-estimated or the conditions in the Solway must be very different from what they are further south. This may be judged by the following extract from a letter written by Mr. Ascroft in 1889. I may say that this gentleman (who is now, I am glad to say, a member of the Lancashire Fishery Committee) has had a long and practical experience in all kinds of sea-fishing on the Lancashire coast, and is a careful and accurate observer. He writes as follows:-"Shrimping destroys more young fish than almost any other agency. I have seen in Formby Channel 10 cwt. of young flukes destroyed, not one the size of half-a-crown, by one boat, and there were sixty boats there that day."

Now, taking the weight of a fluke the size of half-a-crown at oz., a simple calculation will show that each boat captured 35,840 young flukes (a term which includes plaice and dabs) in one day, or 215,040 in a week of six days-nearly twice as many as Dr. Fulton's figures for a year! And elsewhere Mr. Ascroft says: "You may put it as an axiom that 90 per cent. of fish that comes on a boat is destroyed, as when trawling they sail back as they have got their net, and do not commence sorting the take until the net is out again, and they do not, in shallow water, throw the rubbish (i.e. everything except shrimps) over until they turn out to haul, for fear of getting it into the net again." All of which I may say is borne out by my own experience.

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The following is an extract from my diary, written July 10, 1885, when Fishery Committees were not dreamt of. The occasion was an excursion for dredging purposes of the Chester Society of Natural Science, when I took my boat and trawl to meet their steamer at the mouth of the Dee. The Green Buoy marks the bar near Prestatyn, and I let down the trawl in midchannel (about 5 fathoms) in the hope of getting some natural history specimens:-"Began to trawl just below the Green Buoy. Got a few goodish soles, and an immense number of young soles, which always squeeze their heads through the meshes. (N. B.-Shrimp-trawling at this time of year should only be allowed within a quarter of a mile of the shore, to avoid the immense destruction of fry, which mostly lie further out.) Afterwards got a good haul of shrimps as close in (shore) as we could go." I have a perfect recollection of the occasion, and although the trawl was only down about twenty minutes I was horrified at the number of young soies which were in the net, and most of which had choked themselves. But there were very few shrimps, which mostly lie in very shallow water near the edge of a sand-bank.

As a remedy for this destruction I would suggest that the principal breeding-grounds be ascertained, and trawling on them prohibited at such times as the young fish are there. If the prohibition be evaded, then a steamer-load of very large angular stones, distributed from 100 to 200 yards apart on the selected grounds, would effectually prevent trawling, and at the same time, as they became covered with weed, afford shelter and food to the fish and shrimps. This has been done by Nature in this bay, where large boulders washed out of the drift that here forms the coast-line strew the shore at wide intervals, and render trawling for shrimps impossible, though hand nets can be and are worked.

I trust the importance of the subject will excuse the length of this letter. ALFRED O. WALKER. Nant y Glyn, Colwyn Bay, December 14.

The Salts in Natural Waters.

THE inquiry of your correspondent "R. B. H.," in NATURE of November 26 (p. 78), may be answered as follows. In the analysis of an ordinary water, after determining the respective amounts of lime, magnesia, (soda), carbonic acid (combined), sulphuric acid, nitric acid, and chlorides (these being the constituents met with usually in such a water), we proceed to combine the acids and bases thus: the carbonic acid is calculated to carbonate of

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Now, although this is the usually accepted and conventional method of returning an analysis, there is no doubt that the assumptions it involves are altogether arbitrary, illegitimate, and unscientific. The only scientific method of returning a water analysis is to represent (in parts per 100,000; not in grains per gallon, as the atrocious English system of weights and measures generally compels us to) the constituents actually found; as, for instance,

CaO; MgO; CO2 ; N,O5; Cl; &c.

This is all that an analyst is entitled to say, and this much is certain when we proceed to combine the constituents, we are dealing in conjecture.

Unfortunately, however, it seems to be a "law of Nature" that those classes of the community who chiefly require the services of analysts are absolutely ignorant of the merest rudiments of chemistry; the consequence is that if any analytical purist endeavours to reform upon the conventionally established procedure, and to return a certificate of analysis in a scientific manner, his clients are up in arms at once, and indignantly demand what he means by sending them such a nonsensical rigmarole.

Thus far, then, we are helpless; but it is most undesirable that this conventional procedure should be adhered to whenever it is possible to substitute the scientific (as in an analysis of purely scientific interest).

"R. B. H." asks what salts really exist in solution.

According to Ostwald and others, no salts at all if the solution be dilute enough, but only dissociated ions with electrical charges. But whether this theory be correct or not, it is improbable to the last degree that an analysis represents the salts actually present. The indeterminateness of the problem is clearly shown by the fact that from the same solution either sodium chloride and magnesium sulphate, or sodium sulphate and magnesium chloride, may be obtained, according to the method of crystallization adopted. Even supposing that Ostwald's theory be incorrect, and that not ions but salts exist in solution, and that these different results be due to double decomposition occurring in one case, it would be a gigantic assumption that we can definitely show the exact natural distribution in a complicated solution containing eight or ten constituents.

If "R. B. H." wishes to see an account of how acids and bases distribute themselves in a simple solution, he may consult Ostwald's "Outlines" (p. 338, &c., English translation), and also the discussion on avidity in Lothair Meyer's "Modern Theories of Chemistry" (472-87). F. H. PERRY COSTE, 7 Fowkes Buildings, Great Tower St., E. C., Nov. 28.

I AM much indebted to Mr. Perry Coste for his clear and candid answer to my question. It is exactly the answer which I anticipated. The actual facts established by analysis are too often forced, by the arbitrary assumptions of the analytical chemist, to yield unwarrantable conclusions.

The reason given is, that "the people love to have it so." I had hoped that chemists could give some better grounds for their proceedings. They bring to mind the words of the old prophet: "A wonderful and horrible thing is come to pass in the land; the prophets prophesy falsely,' .. for "my people love to have it so; and what will ye do in the end thereof?" Surely we may henceforth claim, in the interests of truth or (which is the same thing) science, that chemists will give us in every case the actual facts obtained by analysis; and if they proceed further for the sake of the prejudices of the ignorant, they will at least warn them that such further inferences are not trustworthy, and have only a very moderate amount of probability, if they can even lay claim to any probability at all.

I speak feelingly, because I have had occasion to examine a great number of analyses of water from the chalk of the London Basin, telling me, in most cases with a "cocksureness" which has amazed me, what salts, and what amount of them, these waters contained, and these, for purposes of comparison, I have

had painfully to reduce back to the real facts from which they were derived.

I am quite prepared to believe that the investigations of Ostwald and others as to solutions show that salts as such do not exist in these waters at all, and that the relations of acids and bases in such cases are variable with the physical condition of the water. As an instance which has come under my own notice, it was reported by competent chemists, with reference to water from a deep well in Harrow, in which an unusual quantity of magnesium and sulphuric acid was found, that at 60° F. its hardness was 10°4 (grs. per gall.); that, mixed with an equal quantity of distilled water, its hardness rose to 24°; while at the temperature of 158° it rose to 26°5. I suppose that a chemist would hardly attempt to assign with much confidence what exact changes in the relations of the dissolved constituents would produce these and similar results. All the more reason, then, why analysts should limit themselves to statements which they can vouch for by direct observation and the balance. My remarks having extended beyond a mere question, I think it best to sign myself in full, ROBERT B. HAYWARD.

Peculiar Eyes.

MR. SHAW's case is by no means so peculiar as he supposes. I imagine that everyone who has had to do with experimental questions of physiological or psychological optics has found it to be rather the exception than the rule that an investigation of his reagents' eyes has shown their perfect equality-as regards "long and "short "sight, colour sensitivity, and sensitivity to light. The common preferential use of one eye explains a good deal (cf., e.g., Aubert, Physiol. d. Netzhaut," p. 18; Schön, Arch. f. Ophthalmologie, xx. 2, p. 271). Mr. Shaw may also be colour-blind in one eye; the perception of colour difference alone is no criterion. I find it safest to employ the wool, spectrum, and coloured-card tests in combination.

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Animals (with the exception of the very highest) have normally a so restricted binocular vision that they need not be taken into account.

It may be interesting to note that a like difference of sensational capacity exists between the two ears. A tuning-fork held to one ear may, quite normally, drown a tone-sensation which is half a musical tone deeper or higher than that excited by the same fork in the other ear. E. B. TITCHENER. P.S.-I discovered the very considerable inequality of my own eyes quite accidentally in my sixteenth year.

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Alleged Pseudopodes of Diatoms.

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WILL you allow me to express my concurrence in your criticism (p. 140) on Mr. Grenfell's paper on the occurrence of pseudopodia in the Diatomaceous genera Melosira and Cycletella? I express no doubt on the accuracy of Mr. Grenfell's observations, the knowledge of which I have derived from his paper in the Quarterly Journal of Microscopical Science, and from his verbal description at a meeting of the Linnean Society; but I do desire to enter my protest against the use of the termi pseudopodia for the protoplasmic filaments observed by him. According to the accepted meaning of this term, it is applied to masses of protoplasm which are in organic connection with the protoplasm of the body of the organism, and which are retractile. I understand Mr. Grenfell that he is unable to affirm either of these facts with regard to the structures observed by him; and, until this is done, the application to hem of the term "pseudopodia" appears to me to involve a begging of the question at issue, and a needless and regrettable confusion in terminology. ALFRED W. BENNETT.

Intelligence in Birds.

UNDER this head Mr. Wilkins, in your last impression (p. 151), speaks of Podoces panari hiding food in the sand.

I have

a fox-terrier puppy which was taken from its mother when about seven weeks old, and sent to me. I have no other dogs, nor has he seen any dogs, but he buries bones in the garden with great skill, digging a hole with his fore-paws. He puts in the bone, and carefully pushes it down with his nose, and then covers it with garden soil, which is pushed in with his nose. The work is very carefully and elaborately well done.

I have had, at various times, very many dogs of all kinds and ages, but I never saw so young a puppy bury bones, or any dog do it so well. It is an admirable example of pure heredity. Norfolk Street December 19. JOE.

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General Williamson consulted me as to the probable value of the so-called mine of "pure metallic iron," stating, on the authority of the prospector, that the vein had been traced for a distance of about two miles, that it was 40 yards wide in places, finally disappearing into a mountain, and that a car-load could be taken from the surface and shipped with but little trouble.

A glance at the peculiar pitted appearance of the surface, and the remarkable crystalline structure of the fractured portion, convinced me that the fragment was part of a meteoric mass, and that the stories of the immense quantity were such as usually accompany the discovery of so-called native iron mines, or even meteoric stones. As soon as possible, in June, I made a visit to the locality, and found that the quantity had, as usual, been greatly exaggerated.

There were some remarkable mineralogical and geo

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bottom seemed to be from 50 to 100 feet (15'24 to 30 48 metres) below the surrounding plain. The rocks which form the rim of the so-called "crater are sandstones and limestones, and are uplifted on all sides at an almost uniform angle of from 35° to 40°. A careful search, however, failed to reveal any lava, obsidian or other volcanic products. I am therefore unable to explain the cause of this remarkable geological phenomenon. I also regret that a severe gallop across the plain had put my photographic apparatus out of order, so that the plates I made were of no value.

About two miles (3.22 kilometres) from the point at the base of the "crater" in a nearly south-easterly direction, and almost exactly in a line with the longest dimensions of the area over which the fragments were found, two large masses were discovered within about 80 feet (24:38 metres) of each other. The area over which the small

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logical features which, together with the character of the iron itself, would allow of a good deal of self-deception in a man who wanted to sell a mine.

Description of Locality.-Nearly all of the small fragments were found at a point about ten miles south-east from Cañon Diablo, near the base of a nearly circular elevation which is known locally as "Crater Mountain." I believe this is the same as Sunset Knoll, figured on the topographical sheets of the U.S. Geological Survey. This is 185 miles (297'72 kilometres) due north from Tucson, and about 250 miles (402 34 kilometres) west of Albuquerque.

The elevation, according to the Survey, rises 432 feet (13167 metres) above the plain. Its centre is occupied by a cavity nearly three-quarters of a mile (12 kilometres) in diameter, the sides of which are so steep that animals that have descended into it have been unable to escape, and have left their bleached bones at the bottom. The

masses were scattered was about one-third of a mile (0'53 kilometre) in length, and 120 feet (36'57 metres) in its widest part. The longer dimension extended north-west and south-east.

Description of the Specimens.-The largest mass discovered weighs 201 pounds (91171 kilos), and, as the photograph shows (Fig. 1), has a somewhat flattened rectangular shape, showing extraordinarily deep and large pits, three of which pass entirely through the iron. The most remarkable example of such perforation is the Signet Iron from near Tucson, Arizona, now in the National Museum, and figured in Prof. F. W. Clarke's Catalogue.1

1 The Signet Iron was discovered about 30 miles (48 28 kilometres) from Tucson. Dr. Geo. H. Horn states that twenty-five years ago he was told by the Spaniards that plenty of iron could be found on a range of hills extending north-west and south-east half-way between Albuquerque and Tucson.

One other large mass was found weighing 154 pounds (69.853 kilos). This is also deeply pitted. A mass weighing approximately 40 pounds (18:144 kilos) was broken in pieces with a trip hammer, and it was in cutting one of the fragments of this mass that diamonds were discovered (Fig. 2).

Besides these masses of considerable size a careful search made by myself with the assistance of five men was rewarded by the discovery of 108 smaller masses. Twenty-three others were also discovered, making a total of 131 small masses, ranging in weight from of an ounce (179 grm.) to 6 pounds 10 ounces (3'006 kilos). A brownish-white, slightly botryoidal coating, found on a number of the meteorites, is probably aragonite.

1

A thorough examination of many miles of the plain proved that the car-load of iron existed only in imagina- | tion. Accompanying the pieces found at the base of the "crater" were oxidized and sulphuretted fragments which a preliminary examination has shown are undoubtedly of meteoric origin. About 200 pounds (90718 kilos) of these were secured, from minute fragments up to 3 pounds 14 ounces (1757 kilos). These fragments are mostly quite angular in character, and a very few show a greenish stain, resulting probably from the oxidation of the nickel. This oxidized material is identical in appearance with an incrustation which covers some of the iron masses and partially fills some of the pits.

Composition. After obtaining the meteorite I was unable to return to Philadelphia for some time, and therefore sent a frag nent of the 40-pound mass (18 144 kilos) to Prof. G. A. Koenig for examination. Prof. Koenig was compelled to leave town before this examination was completed. I take the following, therefore, from his letters to me, and from an account furnished the daily Public Ledger by Dr. E. J. Nolan, Secretary of the Academy of Sciences, of a preliminary notice made by Prof. Koenig, June 23, before the Academy of Natural Sciences of Philadelphia. In this account he says:

"In cutting the meteoric iron for study it had been found of an extraordinary hardness, the section taking a day and a half, and a number of chisels having been destroyed in the process. When the mass, which on the exterior was not distinguished from other pieces of meteoric iron, was divided, it was found that the cutting apparatus had fortunately gone through a cavity. In the attempt to polish the surface, so as to bring out the characteristic Widmannstättian figures, Dr. Koenig received word that the emery wheel in use had been ruined.

"On examination, he then found that the exposed cavities contained diamonds which cut through polished corundum as easily as a knife will cut through gypsum. The diamonds exposed were small, black, and, of course, of but little commercial value, but mineralogically they are of the greatest interest, the presence of such in meteorites having been unknown until 1887, when two Russian mineralogists discovered traces of diamond in a meteoric mixture of olivine and bronzite. Granules of amorphous carbon were also found in the cavity, and a small quantity of this treated with acid had revealed a minute white diamond of one-half a millimetre, or about 1/50 of an inch in diameter. In manipulation, unfortunately, this specimen was lost, but others will doubtless be obtained in the course of investigation. The minerals troilite and daubreelite were also found in the cavities. The proportion of nickel in the general mass is 3 per cent., and the speaker was not as yet able to account for the extraordinary hardness apart from the presence of the diamonds in the cavities."

1 October 18.-During September I received three additional large masses weighing respectively 632, 506, and 145 pounds (or 286 678, 229'516 and 65 771 kilos). The two latter were each perforated with three holes. A number of smaller masses up to 7 pounds (3175 kilos) were discovered by digging. The three large masses and one of 23 pounds (10'432 kilos) were covered with grass and earth.-A. E. F.

Prof. Koenig in a letter to me gives the following points as definitely known :

"(1) Diamonds, black and white, established by hardness and indifference to chemical agents. (2) Carbon in the form of a pulverulent iron carbide occurring in the same cavity with the diamonds. The precise nature of this carbide, whether containing hydrogen and nitrogen, is not ascertained, except in so far that after extracting all iron by nitro-hydrochloric acid the black residue goes into solution with deep brown colour upon treating it with potassium or sodium hydrate. From this solution acids do not precipitate anything. (3) Sulphur is not contained in the tough malleable portion of the meteorite, but in the pulverulent portion. (4) Phosphorus is contained in the latter, and not in the former. (5) Nickel and Cobalt in the proportion of 2:1 are contained in both parts nearly equally. (7) Silicon is only present in the pulverulent portion. (8) The Widmannstättian figures are not regular. (9) The iron is associated with a black hydroxide containing Fe, Ni, Co, P, in the ratio of the metallic part, and therefore presumably derived by a process of oxidation and hydration of the latter." Conclusions. As this meteoric iron contains only 3 per cent. of nickel, while that from the Santa Catarina Mountains, 30 miles (48 28 kilometres) south-east of Tucson and 215 miles (346 kilometres) from this locality, contains from 8 to 9 per cent., according to the analysis of Brush and Smith, they are quite distinct, although somewhat alike in external appearance. They also somewhat resemble the Glorietta meteoric irons from about 300 miles (482 8 kilometres) to the east-north-east, in New Mexico. These contain 1115 per cent. of nickel.

The most interesting feature is the discovery for the first time of diamonds in meteoric iron.1 This might have been predicted from the fact that all the constituents of meteoric iron have been found in meteoric stones, and vice versa, although in different proportions.

The incrustation of what is probably aragonite shown by some of the masses has rarely been noticed (I find two records by J. Lawrence Smith which he states to be unique, and both of these were from regions south of this one). The incrustation is especially interesting as showing that the meteoric irons must have been embedded a long time, as the formation of aragonite would be exceedingly slow in this dry climate.

The remarkable quantity of oxidized black fragmental material that was found at those points where the greatest number of small fragments of meteoric iron were found would seem to indicate that an extraordinarily large mass of probably 500 or 600 pounds (226 796 or 272 165 kilos) had become oxidized while passing through the air, and was so weakened in its internal structure that it had burst into pieces not long before reaching the earth.

THE SEVERE GALE OF NOVEMBER 11. THE HE storm which traversed England on November II was one of the most severe of recent years. It resulted in considerable loss of life and property at sea on our coasts, and did a large amount of damage on land.

The weather over England at the commencement of the month was dry and fine, and the conditions were those known as anticyclonic, the barometer on November 5 having exceeded 307 inches over a great part of the United Kingdom. On November 8, the type of weather became cyclonic, and disturbances were skirting close to our coasts from off the Atlantic, south-westerly gales being experienced in the Hebrides and in the west of Ireland;

Attention may be called to the discovery by Haidinger (1846) of cubic crystals of a graphitic carbon in the Arva meteoric iron, and also of somewhat similar crystals from the Youngdegin (West Australia) iron, described by Fletcher (1887) under the name of cliftonite. Both have been regarded as pseudomorphs after diamond.

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