20 



SCIENCE. 



outside light. A lieberkuhn is furnished with the glass 

 which can be screwed on in place of the cap while exam- 

 ining opaque objects. The speaker had not had the glass 

 in his hands long enough to become perfectly acquainted 

 with all its qualities, it certainly is a good one, however. 

 It resolves angulatum very satisfactory, and bears eye- 

 piecing extremely well, working admirably on anatomical 

 structures. 



The lieberkuhn seems to be a valuable addition for 

 some sorts of study as it brings out surface workings with 

 unusual clearness, even in transparent objects. Mr. E. B. 

 Stuart exhibited a Hitchcock lamp which he stated com- 

 mended itself to the use of microscopists. No chimney is 

 required, it being a blast lamp, the flames of which is 

 fanned by a passage of air from the bottom, the top of 

 the lamp driven by a noiseless clockwork. The oil well 

 is entirely separate from the outside part of the lamp, and 

 is kept cool by the cold blast of air constantly surround- 

 ing it. It gives a light of about a six-foot gas burner and 

 the flame is steady and more free from flicker than gas or 

 the ordinary carbon burner. He also showed under the 

 microscope specimens of the gelatine-bromide plates for 

 photographic work, that had been submitted by a photo- 

 grapher as imperfect. An inspection under the micro- 

 scope showed three kinds of spots. One caused by dust 

 panicles which had settled on- the gelatine while still soft, 

 and as the emulsion hardened, became- firmly fixed on the 

 plate. The second kind of spots were caused by, appar- 

 ently, the solvent action of some substance on the film, as 

 it could be seen to be less dense at those points, 

 while the third were thicker and evidently caused 

 by carelessly spattering the emulsion on partially dried 

 plates. 



The meeting was then declared informal. 



Wm. HOSKINS, Secretary. 



THE AMERICAN CHEMICAL SOCIETY. 



The papers appointed to be read on the evening of the 

 December meeting were, owing to the election of officers, 

 omitted and therefore at the Conversazione held on Dec. 

 16 they were again brought up for consideration. 



The first and second papers were " On the Separation 

 and Estimation of Manganese" and "On a Modification 

 of Mohr's Burette ; adopting it to use in delivering cor- 

 rosive solution " by Nelson H. Barton. Both of these 

 papers consisted of descriptions of details of manipulation 

 which the author had been lead to use in his own labora- 

 tory resulting from his experience and which under favor- 

 able considerations might be desirable to employ. 



The third paper was by Mr. Casamajorand titled " An- 

 alysis of Soghum Juice" an enumeration of the results 

 obtained by him in his laboratory with comments on them. 



" A new Laboratory Filter and Aspirator " was the 

 next paper, also by Mr. Casamajor. The apparatus re- 

 ferred to has recently been patented, and in the above 

 paper it was thoroughly desciibed and a model exhibited. 

 The fifth paper was by Dr. A. R. Leeds, entitled " A 

 Chemical Inquiry into the Self-purifying Power of a Flow- 

 ing Stream." In this paper the complete results of the 

 work done by Dr. Leeds for the New Jersey Board of 

 Health were presented. It will be recollected that in a 

 previous number a synopsis of this paper was given to 

 the readers of SCIENCE. On the present occasion charts 

 were exhibited showing the exact relations existing be- 

 tween the various estimations which were made. These 

 were peculiarly interesting to chemists although unfor- 

 tunately the entire subject of water analysis is in such a 

 state of confusion that it is difficult to make much head- 

 way in the accumulating and conflicting mass of literature 

 which is current on this subject. The entire paper of 

 Prof. Leeds will be published in the N.J. Hoard of Health 

 Reports. The final paper of the evening was " A Nev/ 

 Method for the Analysis of Mustard by the same gentle- 

 man with the assistance of Mr. Everhart. The ordinary 



methods given by Hassall, Blyth and others were so un- 

 satisfactory in their results that an effort was made to 

 produce something more definite. After some little study 

 it was found best to separate the various constituents by 

 different extractions with various reagents, so that an 

 addition to the conventional determinations of moisture, 

 oil and ash ( for the mineral adulterants ) extractions of 

 alcohol and ether are made for the remaining ingredients. 



M. B. 



SUICIDE, an Essay on Comparative Moral Statistics. 

 By Henry Morselli, M. D., Professor of Psycho- 

 logical Medicine. Royal University, Turin. Being 

 abridged from the original, as Volume XXXVI of 

 the International Scientific Series. New York. D. 

 Appleton & Co. 

 The present moment seems peculiarly favorable to the 

 presentation of a work on the subject of suicide. Whether 

 it tie the great accumulation of financial and political crises, 

 or the increase of mental derangements, or a fundamental 

 change in the morale of the civilized races, it would seem 

 as if a great suicidal wave was sweeping over our social 

 hcrizon. The labors of Buckle, Wallace and Bagshot 

 have taught the necessity of studying such complicated 

 problems synthetically. The statistics of no one com- 

 munity, the analysis of no one cause, will suffice to ex- 

 plain their phenomena. Professor Morselli, fully recog- 

 nizing this fact, has undertaken a study of the question 

 of suicide from a statistical point of view, and one involv- 

 ing in its analysis the results of Social Scientific, Anthro- 

 pological, and Medico-Psychological inquiries. 



The first fact demonstrated by a careful study of statis- 

 tics is the regularity and the increase of suicide in civil- 

 ized countries, which finds its expression in the painful 

 conclusion, that " in the aggregate of the civilized States 

 of Europe and America, the frequency of suicide shows 

 a growing and uniform increase, so that generally, volun- 

 tary death since the beginning of the century has increased 

 and goes on increasing more rapidly than the geometrical 

 augmentation of the population and of the general mor- 

 tality." 



Among individual elements serving to explain this 

 increase of suicide, climate deserves the least prominence 

 as a direct factor. The only ascertained fact in this direction 

 is that in the centre of Europe on an area of about 942, 

 000 square kilometers comprised between 47-57 of lati- 

 tude and 20-40 of longitude, are found the people who 

 manifest the greatest inclination to suicide. The least 

 amount of suicide is found on the isothermal line of + 17.° 

 5 C, running through Portugal, Spain, Italy, Corsica and 

 probably Greece. That the mere feature of temperature 

 is not a very impoitant one, is shown by the fact that on 

 the isothermal line of + io° C, there is the greatest vari- 

 ation. In the United States for example the suicidal rate 

 is 35 per million ; in Ireland 16, in England 67, in Bel- 

 gium 55, the Netherlands 35, Hanover 140, Prussian Sax- 

 ony 228, Galicia 98. A more direct and constant relation 

 is found with other cosmical influences, thus the regions 

 of the great rivers are most afflicted by suicide coeteris 

 paribus, while on the contrary marshy or excessively low 

 lands, like the Landes in France, the low countries about 

 the Zuyder Zee and Jutland, show a lesser proportion. 

 That suicide is most frequent in the warm seasons, is con- 

 firmed by Morselli, this observation is a familiar one to 

 New Yorkers. In our city a perfect suicide furore occurs 

 in certain summers, and the direct influence of the heat 

 has no doubt much to do with this as with the summer 

 increase in violent crimes similarly the results of insanity 

 or passion, a fact to which, however, no reference is made 

 by the author before us. It is certainly a noteworthy 

 fact, in which he confirms Guerry, that the maximum of 

 suicide falls under the summer solstice, the minimum un- 

 der the winter solstice. 



