A B S 



tlioilty of Albiiius, to abforb by fuction. The pro- 

 bofcis of the papiHonaceous flies afts in the fvime man- 

 ner And the ahforbents of the echinus niarinus have 

 this power in fo great a degree as to enable the animal 

 firmly to attach itfelf to any fnbflance which it may hap- 

 pen to touch. It may be right to remind the reader that 

 the difficulty in accounting for the funftion of thife veffels 

 exifts only at its commencement, for when the imbibed. mat- 

 ter has gone beyond the fnft va've it mufl proceed, and it 

 will be powerfully carried forward by the contraftile force of 

 the veird, and by every occafional preifure which is applied 

 to it. Some phyfiulogifts believe that the abforbents can- 

 not take up any matter that is not flu'd. If this opinion 

 were true, the folids of our bodies muft be converted into 

 fluidf before they could become fubjetts for abforption. A 

 fmall addition of phofphoric acid might indeed render the 

 earth of bones folublt, and it is in this ftate, that it is car- 

 ried out of the circulating fluids by the urinary feereticn. 

 No liquid has been conceived capable of diflblving fuch fol'ds 

 as compofe the mufcular fibres, but one that refembles in 

 qualities the gaftric juices. Dr. Stringham, in his Thefis on 

 theabforbing vcfTelspubhlhcd in Edinburgh, and Mr. Smith in 

 London, imagined they had difcovercd that fuch a fluid cap- 

 able of diffolving fiefli, could be fecreted in various parts of 

 the body. See Duncan's Med. Com. vol. x. p. ^j.i. Sub- 

 fequent experiments have, however, been followed by con- 

 trary confequenccs. See Dr. FuUarton's Thefis on abforp- 

 tion, publillied at Glafgovv, A. D. iSoo. Indeed it is un- 

 like the fimplicity obfervable in other parts of the anim.al 

 occonomy, (hould fuch a double fecretion take place ; firft, 

 the fecretion of folid materials to compofe the ftrudlure of 

 the body, and then the fecretion of a fluid to diflblve them. 

 It feems beft in fuch difficult inveftigations to note fafts 

 rather than to form theories, and whoever contemplates the 

 things done in the animal body v/iU be aftonifhed at the 

 powers of the veffels by whole agency they muft be effefled. 

 As an inftance, the following may be mentioned. A whole 

 bone may perifh, it may be encafed by a new one ; and by 

 the vafcular lining of the new bone, the original dead bone 

 may be altogether removed. 



Absorption, in Chem'iflry. It is a well known chemical 

 faft, in moil cales of combination of gafTeous fubftances, 

 either with other gafles or with liquids or folids, that a very 

 confiderable diminution of volume is experienced. This 

 effeft is called abforption, to diftinguifh it from the de- 

 creafe of bulk occafioned by condenfation. The condenfa- 

 tion of a gas, whether by mechanical preffure, or by lower- 

 ing its temperature, merely increafes its fpecific gravity, 

 without dcftroying that ftate of elaftic fluidity which is 

 eftential to its exiftence as a gas. On the contraiy, the ab- 

 forption of a gas implies fuch an Intimate union with the ab- 

 forbent as wholly deftroys its gaflTeous ftate of exiftence, and 

 reduces it to a liquid or a folid. Thus carbonic acid and 

 ammoniacal gaffes, if inclofed in feparate veffels, may be 

 condenfed, by mechanical means, till they are of much 

 greater fpeciflc gravity than ordinary, but yet retaining all 

 the phyiical properties of air : as foon however as thefe 

 gaffes are brought into contaft with each other, a great 

 abfoi-ption takes place, and a folid is produced containing 

 all their gravitating matter, but wholly deprived of the 

 effential charatler of a gas. - . 



In pneumatic chemiftiy, or that branch of the fcience 

 which treats of the aeriform fubftances, the apparatus for 

 containing the gaffes confifts of jars or other glals veffels in- 

 verted in water or quickfilvcr ; now on account of the great 

 difference in fpecific gravity between thcfe fluids, whenever 

 a jai: partly filled with air, and the reft of its capacity with 



ADS 



« 



quickfilvcr, is transferred from a Lafon of quickfilvcr to one 

 of water, the metal defcends, and ir. replaced by a cohimn 

 of water, at the fiune time that .".n apparent abforption takt» 

 place: this fallacy lias no doubt often vitiated the rcfults of 

 experiments, and therefore defeiTcs to be particularly cau- 

 tioned againft. For example, if an inverted jar 14 inelus 

 higii, contains eight inches of air, and fix of mercury, (the 

 barometer ftanding at 30°,) the preflurc of the atmi.ii.hcre 

 on the confined air is = 30 inches of mercuiy — 6 inclies=: 

 24 inches ; but if the jar, with its contents, be removed into 

 a bafon of water, the quickfilvcr finks do.wn and is replaeed 

 by water, in confequcnce of whieli the atmofplierieul pref- 

 lurc on the confined air becomes =30 inches of mercnr)- — 

 6 inches of luahr, or (the fpecific gravity of mercurj' to 

 water being 14: l) = 29.572 inches. The difference 

 here amounts to full one fixth of the whole atmofphcric prof- 

 fure, and therefore the inclofed air occupies Icfs fpacc than 

 before, although no real abforption has taken place. Sec 

 Pneumatic Chimtjlry. 



Absorption of the earth, in Natural H'ljlory, a term 

 uf>jJ by Kircher and others, for the finking in of large tracts 

 of land, by means of fubten-aneap commotions, and many 

 other accidents. 



Pliny (Hlft. Nat. tom. i. p. 115. Ed. Hard.) tells us, 

 that in his time the mountain Cybotus, with tlie town of 

 Curites, which flood on its lide, were wholly abforbcd 

 into the earth, fo that not the leaft trace of cither re- 

 mained : and he records the like fate of the city of Taiitalis 

 in Magnefia, and after it of the mountain Sypilus, both thus 

 abforbed by a violent opening of the earth. Galanis and 

 Gamales, towns once famous in Phoenicia, are recorded to 

 have fliared the fame fate : and the vaft promontor)-, called 

 Phegium, in .^Ethiopia, after a violent earthcpiake in the 

 night-time, was not to be feen in the morning, the whole 

 having difappeared, and the earth having clofed over it. 

 Thefe and many other hiftories, atteftcd by authors of 

 greateft credit among the ancients, abundantly prove the 

 fail in the earlier ages ; and there have not been wanting 

 too many inftanees of more modem date. Kiiehcr's Mund. 

 Subter. p. 77. 



The mountain Picus, in one of the Molucca Ifles, was fo 

 lofty, that it appeared at great diftances as an immenfe co- 

 lumn reared ere£t in the air, and feived as a land-mark to 

 failors ; an earthquake in this ifland deftroyed it ; at one 

 inftant the whole mountain was abforbed into the bowels of 

 the earth, and no mark of Its place remained, but a vail 

 lake of water exacUy anfwering to the fliape of the bafc of 

 the mountain. A like accident, but of a more terrible 

 kind, happened in China, in the year 1556, when a whole 

 province of the mountainous parts of that kingdom was in 

 one moment abforbed into the earth, and all the towns buried, 

 the whole number of the Inhabitants finking with it, and an 

 immenfe lake of Vv'ater rem:il:.ing in its place to this time. 

 Of much later date is the deftruction of a city in the con- 

 fines of Switzerland : but this, though generally faid to have 

 been fvvallowed up into the earth, was not properly an ab- 

 forption, for the whole city was buried by the tall of a 

 mountain upon it. 



The burning mountain?, Vesuvius and Stroncylus, 

 both once very high, have in length of time loft half their 

 height, the upper part having been midennined by the 

 burning, and having fallen into, and been abfoibed by the 

 under part and the fea. And in the year 1^46, du'-ing the 

 terrible .earthqu;ike in the kingdom of Chili, fcve-al whole 

 mountains in the Andes difappeared, and were one after 

 another wholly abfoibed In the earth. 



Thefe, and a thoufand other accidcr.ts of the like kind, 

 z prove 



