B L O 



fequent chemifts. Partjientier and Deyeux fuppofed, that the 

 red colour depended upon the union of iron with the oxygen 

 contained in the blood ; Fourcroy and VauqueUn, who fuc- 

 ceeded, denied this, and aflerted that it depended upon the 

 fubphofphate of that metal. Dr. Wells, however, fo long ago 

 as the year I797) caUed this opinion in queftion, andafferted 

 that the moft delicate tolls of iron did not indicate the pre- 

 fence of that metal in the blood ; that otiier red fubftances 

 do not ail contain iron ; and that, on the other hand, other 

 fubftances that do contain iron are not red. Hence he fup- 

 pofed, that the red pai-t of the blood was an organized 

 animal fubftance. This opinion has been lately revived by 

 an eminent modern chemift, Mr. Brande ; who afferts, con- 

 trary to almoft every other chemift, that the colouring 

 matter of the blood yields no more iron when burnt than 

 any other conftituent of the blood, and that confequently 

 it cannot owe its colour to that principle. Berzelius, how- 

 ever, though he denies the opinion of Fourcroy and Vauque- 

 hn, that the red colour depends upon a fait of iron, agrees 

 with moft preceding ch&mifts, that its afhes contain much 

 more of this metal than thofe of either its other conilituents, 

 that is to fay, that they contain ^o per cent, of oxyd of iron, 

 while the allies of albumen and fibrin do not yield a trace 

 of that metal. Hence he concludes, that iron, fomehow 

 or other, and in a manner unknown to us at prefent, pro- 

 bably conduces to the colour of the blood. The opinion of 

 Berzelius, and moft modern chemifts, refpefting this prin- 

 ciple is, that it clofely refembles albumen and fibrin in its 

 properties. According to Berzelius, the mineral acids acl 

 upon it nearly in the fame manner as upon albiunen. It is 

 foluble alio in dilute acetic acid, and precipitated by the 

 prufliate of potafh, hke that principle ; and hence Ber- 

 zehus is incUned to confider it as a modification of 

 albumen. Vauquelin has lately given a method by which 

 he thinks the colouring principle may be feparated from 

 the other principles of the blood, which is a very di£S- 

 cult talli ; we do not think, however, that he has been fuc- 

 cefsful. 



Mr. Brande tried to form a lake, by precipitating its acid 

 folution by means of different earthy and metallic falts. 

 Neither alumina nor oxyd of tin anfwered the purpofe well. 

 Corrofive fublimate or nitrate of mercury fucceeded beft. 

 Thefe gradually precipitated the colouring matter, and 

 formed with it powders of a good red colour, not altered by 

 expofure to the air. Mr. B. likewife made fome attempts 

 to employ it as a principle in dyeing, but they were not 

 attended with much fuccefs. 



Some intereiting obfervations have lately been made on 

 the fize of the colouring particles of the blood by Dr. Young. 

 According to this gentleman, they bear no proportion to the 

 fize of the animal. Thus, 



B L O 



cording to the «periments of Gay Luffac and Theoard 

 nbrm is compofed of "cnaru. 



-} 



inch 



The particles ofbullock's blood from 



beef meafured 

 Ditto of a moufe ... 4, ^ 



Do. of human blood ... -j-g,; to < /^ t 

 Do. of blood recently diluted from ) 



fwine - - - - "J ' ' 



Do. of the lliate, about - - Wrr- 



Of the Fibrin. — The experiments of Berzehus jhew that 

 this fubftance clofely refembles albumen in its chemical pro- 

 perties. We do not think it necen"ary therefore to add any 

 thing on the fubjeft here, but refer our readers to the article 

 Albumen. The phyfical properties of fibrin have been 

 already defcribed under Blood in the Cyclopsedia. Ac- 



VoL. XXXIX. 



Hydrogen 

 Carbon 

 Oxygen 

 Azote 



7-021 

 53-360 

 19.685 



19-934 



100 



The btijy coat of blood ujibrin. 



Of the Serofuy.—TKn term has been generally applied to 

 the lalts and animal matters exifting in the ferum of the blood, 

 with the albuminous principle. See tlie defcription oi ferum 

 m the prelent article. '' 



With refpeft to the blood as a whole, little has been added 

 to our knowledge. M. Vogel has attempted to fiiew, that 

 when placed m the vacuum of an air-pump, it gives out a 

 conhderable quantity of carbonic acid : and Dr. Gordon has 

 aLerted, that dunng its fpontaneous coagulation heat is 

 emitted ; but this has been denied by other obfervers, and 

 efpecially by Dr. J. Davy. 



The blood of other animals, and the blood of perfons 

 labouring under different difeafes, have been but little exa- 

 mined ; indeed this extenfive and important field of chemical 

 inveftigation is almoft entirely unexplored. 



BLOOM, in Geography, a townlhip of Pennfylvania, in 



Northumberland county, having 1285 inhabitants Alfo, a 



townfhip of the county of Fairfield, in the diftria of Ohio, 

 having 839 inhabitants. 



BLOOMFIELD. Add— Alfo, a townfhip of Penn- 

 fylvania, in Crawford county, having 114 inhabitants. 



BLOUNT,!. I, infert—Eaft Tenneffee. Add— contain- 



ing 8839 inhabitants, of whom 805 are flaves Alfo, a 



county of the fame ftate, having 3259 inhabitants, including 

 206 flaves. 



BLOW-PIPE. We think it proper to notice here the 

 iniportant modification of this ufeful inftrument, lately con- 

 trived by Mr. Brooke, and which, by the intenCty of the 

 heat it excites, has produced fuch interefting refults in the 

 hands of different experimentalifts, and more efpecially of 

 Dr. Clarke of Cambridge. 



Mr. Brooke's blow-pipe confifts merely of a ftrong copper 

 or iron air-tight box, to which are adapted a condenfing 

 fyringe and jet-pipe, furnifhed with a ftop-cock. Whcu 

 ufed, the box is to be filled with condenfed air by means of 

 the fyringe ; the ftop-cock is then to be turned, and the 

 condenfed air permitted to efcape through the jet. From 

 the fmallnefs of the aperture of the jet, a conftant and uni- 

 form blaft is thus kept up for a confiderable time, (and by 

 the occafional ufe of the fyringe, may be continued for any 

 length of time whatever, ) fimply by means of the elafticity 

 of the air itfelf. 



A great advantage attending the ufe of this blow-pipe is, 

 that the box can be readily filled with any gas, or mixture 

 of gafes, we choofe. Accordingly advantage was foon taken 

 of this property, and a mixture of oxygen and h)-drogea 

 gafes, when inflamed as they iffued from the jet, was found 

 to yield a more intenfe heat than any other. From the 

 habihty, however, of this mixture to explode, great caution 

 was required in ufing it, and this led to the neceffity of 

 fome contiivanee for obviating this dangerous circumftance. 

 Various means were foon fuggefled, mofl of which were 

 founded on the principle recently difcoveredby frrH.Da*-)-, 

 that the inflammation of gafes will not pafs through minute 

 apertures (fee Wire-oal'ze) : and, at length, we beheve 

 iTt the 



