384 



KNOWLEDGE & SCIENTIFIC NEWS. 



[March, 1906. 



colour in the print that corresponds with the red of the 

 orif>:inal. The diflicuhics of working out such a 

 method are such that they might well be regarded as 

 insurmountable. The three dyes must not only be of 

 the correct tints, but they must be fugitive enough to 

 be bleached by an exposure to light of a reasonable 

 duration, and, after the print is made, they must be 

 permanent enough to be but little affected by ordinary 

 light. It is sought to secure these opposing qualities 

 bv adding materials that induce a temporary sensitive- 

 ness, and removng them when the print is made. 



Jan Szczepanik has overcome these difficulties so 

 far that the firm of J. H. Smith and Co., of Zurich, are 

 preparing to issue the .sensitive material commercially. 

 .\t the exhibition of colour photographs arranged by 

 the editors of the BriUsh Journal of Photography at 

 their offices, and which is just about to close, there are 

 a few very striking examples of this process, copies of 

 " lithophanes," that is, the coloured material some- 

 times used for window decoration. The colours in the 

 copies are very clean and bright. Of course, the large 

 flat patches of crude bright colours in the originals are 

 not so .severe a test as more delicate neutral tints, and 

 as the originals are not exhibited it is impossible to tell 

 whether the colours of it are fairly matched in the 

 copies, but it is quite evident that bold colours of very 

 various kinds have been obtained. 



Mr. Cobttrn's Work. — There is an exhibition of the 

 " Work of .\lvin Langdon Coburn " at the house of 

 the Royal Photographic .Society in I'iussell Square, to 

 which anvone is welcome, until the end of March, on 

 presentation of his card. The exhibits are advisedly 

 not called photographs, for we learn from Mr. Bernard 

 Shaw in his preface to the catalogue that Mr. Coburn 

 is very mixed in his methods, making gum prints, for 

 example, on the top of platinum prints. When Mr. 

 Shaw tells us that Mr. Coburn has " condescended to 

 oil painting as a subsidiary study," we are led to ex- 

 pect excellent work in spite of Mr. Coburn 's lack of 

 experience, for he is a young man of only three-and- 

 twenty. The series of some forty portraits is distinctly 

 interesting. They are done in an unconventional style, 

 and although a few of them appear to show- a desire to 

 h^ eccentric, some of them are very fine indeed, and 

 well repay the trouble of a visit to see them. Of the 

 eighty other specimens, Mr. Bernard Shaw appears to 

 consider it necessary to make a sort of apology, for he 

 tells us that Mr. Coburn 's " impulse is always to con- 

 vey a mood, and not to convey local information," but 

 the author himself entitles the most of them by the 

 names of places, streets, bridges, and so on. For my 

 part I cannot imagine them " conveying moods " of a 

 pleasant or satisfactory kind to anyone; their detail- 

 less flat patches, extreme want of definition, and the 

 absence of a sense of due proportion, are distinctly un- 

 pleasing, and the representations of places that I know 

 are useless as reminders. If these pictures were not 

 put forward as serious work — and I suppose that they 

 are meant to be taken seriously — I should have thought 

 that they were a beginner's attempts, with here and 

 there a promise of better things in the future if the 

 maker of them considered it worth while to persevere. 

 It is difficult to l>elieve that these " works " and the 

 portraits in the other room are by the same author. 



Received. — The Thornton-Pickard Catalogue for 

 1906 is to hand, and besides the well-known speciali- 

 ties of the firm, it includes a new pattern of the 

 " Royal " shutter, that is, the roller-blind shutter with 

 the mechanism inside the case, and a low-priced outfit 

 called the " Imperial Perfecta. " 



REVIEWS OF BOOKS. 



Our Stellar Uoiverse. Stereoscopic Star-Charts and Spectroscopic 

 Key Maps. Thomas Edward Heath. (King, Sell and (Jlding, 

 Ltd.). (26-i-vi. with 26 plate.s and 26 stereograms.! los. net. — 

 Changing his view-point, Mr. Heath, instead of imagining him- 

 self at a distance of many light-years from the Solar system, 

 now endeavours to give a ^-dimension idea of the relative 

 distribution of stars as seen from the earth, replacing the 

 celestial sphere for this purpose by 26 regions, which for the 

 purpose of the key maps are represented by tangent planes, 

 one at each pole, eight round the equator, and eight each at 

 latitude 45^ north and south respectively. The corresponding 

 stereograms by the introduction of measured discs, and an 

 allowance for parallax 19,000 times greater than the truth, do 

 represent a system hanging in three dimensions, and the 

 effect is certainly much improved by the piercing of the 

 stereograms to give the stellar appearance not evident on the 

 prints, h special set on thick card is issued at 5s. (or 2s. 6d. 

 to purchasers of the booki. Authorities are given for the 

 values used for parallax of the better determined stars ; for 

 others an average parallax according to spectrum-type is 

 used, which, although it improves the appearance of the 

 stereograms by admitting a larger number of stars, is open to 

 criticism on account of the arbitrary assumption involved. 

 This, however, is of no great consequence, as the scientific 

 value of the stereograms is of much less importance than 

 their popular interest. The spectroscopic key maps give full 

 details as to the name, magnitude, spectrum-type, and parallax 

 of the principal stars, and are meant to enable the purchaser 

 to identify the objects represented in the stereograms, which 

 look far less familiar than the actual stars in the sky. It is 

 unfortunate that the endeavour to cultivate a sense of propor- 

 tion, which is so often lacking nowadays, should be compelled 

 to start with an exaggeration of such a magnitude as i to 

 ig.ooo. Bat the fault is not with the author, whose device is 

 to be commended for its boldness. It is possible that we 

 shall see this principle of exaggeration carried even further, on 

 the ground that the relative proportions are strictly preserved 

 as under a high-power microscope, but the work of Mr. 

 Heath goes as far as appears ad\ isable in that direction. It 

 should be remembered that magnifying the parallax ig.ooo 

 times does not mean observing with eyes 19,000 times the 

 normal distance apart, but with eyes whoss distance apart is 

 19,000 times the diameter of the earth's orbit, or about 34^ 

 billions of miles. 



The Reconstruction of Belief, by W. H. Mallock (Chapman 

 and Hall), price 12s. net. 



This great work, by the author of "Is Life Worth 

 Living," is somewhat disappointing. The enquirer after 

 religious truth, the agnostic requiring enlightenment, the 

 Catholic anxious for confirmation of his early teachings, 

 all are likely to close the book with the feeling that they 

 are not much the wiser than when they opened it. Vet it is 

 all good reading and sensibly written, and if, after a study 

 of it, we are not convinced as to the exact standing and 

 meaning of modern religion, at all events our minds may be 

 opened and our thoughts concentrated on many points well 

 worth considering. 



The author points out that at the root of Christianity are 

 three doctrines, namely, that the universe is over-ruled by 

 some supreme intelligence, who has for his special object 

 the highest good of man ; that each man is a self-directing 

 personalitv, answerable as such to the supreme intelligence 

 for his conduct ; and that his life here derives an infinite 

 importance from the fact that it will be prolonged and com- 

 pleted for better or for worse hereafter. He then adds that 

 even those who are satisfied to let these doctrines go, are 

 conscious of some sort of loss, and desire to find a substitute 

 for them ; whilst others are lookinsj about for some means of 

 defendinsr them, which mav justify them in retaining their 

 faith. It is to this latter class that the present volume is ad- 

 dressed, and thousrh they may derive some comfort and 

 extract many useful ideas", we think it cannot be said that 

 all doubts such as linger in many minds to-day will be 

 eradicated. 



