IM 



CHEMISTRY. 



40 gramme*. If the stain be wetted and toft- 

 eaed by tbwe fluid*, and then examined, white 

 an.l red corpoadea and fibroid particle* will 

 b obacrrcd. 2. In more diffict- It oases, when 

 the microscope, owing to great change* in 

 the hvmatine, can give bat vagae information, 



: -; '- I 1 ..:. . ' I Ml] - - -' 



insults: 



Analfnt.U into an analyzing tube 

 filled with water a few drop* uf* tolutlon of hemo- 

 globin be Introduced till it bu the color of peaeh- 

 tloMcmi, the luminous ray* of the spectrum pawing 

 inmgh Uila laid pre**nt two band* of abtorjitiou 

 between the HIM* D and E of Fraaeubofer, in Uie 

 yellow and the green. Tb **me Cut would be ob- 

 erod If few drop* of blood were substituted for 

 bcooflobin in the analvtis. In oa*e of doubt, 

 tbe h*HDOf lobin of tho blood could be reduced by 

 adding to tbe latter a reducing body. Destroyed 

 hcNBOf lobin h*.. a different spectrum from oxygen- 

 ated haNBOglobin a tingle absorption-band, an Urge 

 M tbe two former band*, and a little to the left of 

 FuMBliufti'i line D. 2. In decomposed blood, or 

 which ha* been treated with acid* or caustic alkn- 

 , hvmoglobln U changed into new substance, 



iatine being formed, which, combined with hy- 

 drochloric add, give* characteristic crystals. We 

 obtain tbeae crystals in tbe following way : A small 

 fragment of dried blood is placed on a glass slide, 

 ana dissolved in * drop of water, * minute portion 

 of *s* salt being added. It is covered with a thin 

 slide, and pure acetic acid is made to pas* between 

 the two slides, and it is heated to boiling-point over 

 * spirit-lamp. Acetic acid U added again, and it is 

 beated afmh ; and this U repeated until the crystal* 

 an obtained. They are rhomboid*!, and of a dirty- 

 brown color. The** two reactions the spectrum 

 examination and tbe crystals of hydrochlorate of 

 hanatine can always be produced with even the 

 n**lllt quantity of blood : and they are so certnin 

 that UM existence of one alone enables us to affirm 

 tbe pTMene* of blood. S. If to a very small quan- 

 tity of blood, dissolved In a little water, you add a 

 few drop* of tincture of naiaoam and of binoxide ot 

 bydrogen, a pen b< sot bin* color is immediately pro- 

 duced ; but. as other organic matter* mucus, sa- 

 liva, etc. g(ve tbe same reaction, this process gives 

 only a probability. The mode of procedure I* a* 

 follows : A tincture of ruaiacum U prepared with 

 aUobol at ST Centigrade, and gnaiacum resin ; a 

 mixture of Mlpborie ether and binoxide of hydrogen 

 is alao mad* and Incloied In a itoppered bottle, and 

 kept ond.r water in the dark. The object stained 

 wttk Mood, If It b* white, i* put Into a little cup, 

 ' rlth water to dissolve out the blc 



being doe, not to the liberation of iodine, 

 l.ut to tbe oxidization of the potassium, the 

 alkali thus formed changing the color of the 

 litmus. The part of the litmus-paper wliirli i- 

 not iodized serves to reveal the accidental 

 pretence in tbe air of alkaline vapors (free 

 ammonia, ammonium carbonate, etc.), which 

 turn the ml litmus-paper blue throughout its 

 entire length ; it is impossible, therefore, to 

 mistake the indications. Moreover, tin- 

 iodized litmus-paper cannot be turned blue by 

 chlorine, bromine, etc., since the chloride and 

 bromide of potassium are neutral. Houzeau 

 states as follows his conclusions, drawn from 

 a large number of observations in various lo- 

 calities, at different seasons of the year : 



1. The air of the country contains an odoriferous 

 and oxidizing principle, which imparts to it pecul- 

 iar odor, and the power of bluing iodized n-d lit- 

 mus-paper; also of decolorizing blue litmus -paper 

 without previously reddening it ; and of destroying 

 certain bad smells. 



2. This principle is ozone. 



8. Ozone exints in the air normally, but the in- 

 tensity with which it acts at any given point of tho 

 le. 



tain, sn.l washed in distilled water; this water U 

 then submitted to the .otion of the re*gcnts. If 

 tb* thing stained be colored, and tbe stein little or 

 not at til Tl.tl.1r, U nitit I I and then 



pre**ed between two or three sheet* of whit. 

 tint-paper, and tried flirt with the guaiacum. If 

 lb* Main be of blood, a mddish or brown ipot will 

 form oa tbe paper. One of the sheet* ihnuld be 

 treated with ammonia, and the Main will become 

 I or rr*n. A second sheet, treated with 

 af gualaaon and osooised ether, will give a 

 4or more or 1*** intense, aconrdlmr t- the 

 It need not be s.1,1, ,1 that 

 Ik*** reaction* will show whether the blood 



_ HoMtwi Me*, a* a reagent for .. 7. .n<>, 



litwuB-paper Imprrpnatrd over half its 

 irCaeewlUi ooe per cent, neutral solution of 

 otMsumiodtd*. In oontart with <itiw. tin- 

 ;* a bltw oolor only in tin- jmrt 

 I wiUi the iodide, tin. change of color 



Mihere is often very variable. 



4. The air of the country contains, at most, about 

 An of its weight, or nV>n of its volume, of ozone. 



6. The manifestation of ozone by the iodized lit- 

 mus-papers is much more frequent in the country 

 than in town. 



6. This difference may be due to the greater cir- 

 culation of air in the fields. 



I. At Bouen the frequency of the ozone manifes- 

 tation* vane* with the seasons, being greatest in 

 spring, strong in summer, weaker in autumn, and 

 still weaker in winter. 



8. The maximum of ozone manifestation occurs 

 in May and June (16 ozone days per month), and 

 the minimum in December and January (4 ozone 

 day* per month). 



9. With respect to the frequency of ozone mani- 

 festation, the meteorological year in our climate* 

 may be divided into two great sensons the very 

 active leuon (cpring and summer), comprising 18 

 ozone days, and the feebly active teason (autumn 

 and winter), including 82. 



10. In general, ozone shows itself most frequently 

 on rainy day* (48 ozone day* in 100 of rain, to 28 in 

 100 of fine weather). 



II. Winds, according to their strength, exert the 

 greatest influence on the manifestation of ozone i :4 

 ozone day* in 100 when the air was calm or but 

 slightly agitated, and 60 in 100 when the air was 

 greatly disturbed). 



IS. At Rouen, the largett number of ozone day* 

 occur* when the wind is from the west or southwest, 

 the smallest number when it is fiom the eaot. 



IS. Most frequently an exaggerated mnnifextation 

 of ozone i in intimate relation to the great si TIM. r- 



El.i rii' perturbations, known as storms, galer, and 

 urricanes. 



14. These great commotions of the stnmsphero 

 act st very great distances. Sometimes they mo- 

 mentarily affect the ozom uf < utire t>w n and local- 

 ities, which, nevertheless, continue to enjoy very 

 fine weather. 



15. Atmospheric electricity appears to be the 

 most active cause of the formation of atmospheric 

 ozone. 



\fif Ozone Generator. This instrument is 

 tlnis ilcHcribed by its inventor, Mr. T. Wills, 

 of the London Chemical Society: "It consists 

 of a piece of glass tube a cylindrical (is pos- 

 sible, with an annular coating of tin-foil on 



