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feveral hours by its own Heat, without any affiftance from the lungs. What is the caufe of this Heat before the lungs act ? How comes it to fail as foon as the lungs play ? Med. Eff. Edinb. Abr. Vol. i. p. 228. feq.
The third opinion is, that the caufe of animal Heat is ow- ing to the adtion of the folid parts upon one another. The heart and arteries move moft, and it is natural to expect, that the Heat (hould be owing to this motion. But even this docs not feem very plaufible, from the following confiderations. 1. The moving parts, however we term them folid, are nei- ther hard nor dry ; which two conditions are abfolutely requi- site to make them fit to generate Heat, by attrition. 2. None of their motions are fwift enough to promife Heat in this way.
3. They have no great change of furface in their attritions.
4. The moveable fibres have fat, mucilage, or liquors every way funounding them, to prevent their being deltroyed, or heated by attrition. Med. Efl". Abr. vol. 1. p. 231.
A fourth caufe afligned for the Heat of our bodies, is that procefs by which our aliment and fluids are perpetually under- going fome alteration.
This procefs, according to Dr. Stevenfon, may be one fui generis^ fomewhat of a middle nature, betwixt fermentation and putrefaction, and he thinks it to come fo near to the latter, that he choofes to call it by that name. In putrefaction, which is a moft powerful diflblvent of bodies, the inteftine action of their minute particles creates, collects, or fome way or other is the caufe or means of Heat. The Doctor thinks it probable, that this procefs is conftantly carried on in all our juices, efpe- cially where there is blood, and this chiefly in the veins ; fo that the blood is both the fountain of Heat, and the firft fpring of metion. He obferves, that it is agreeable to the laws of natural philofophy to reafon on the chemiftry of the animal body, as well as on its mechanics ; the minute component parts of folids having a fet of laws peculiar to them ; and their intimate changes and actions on one another, are not to be accounted, for by the courfer mechanical laws. He obferves laftly, that fmce it has never been demonftrated, that any fluid acquired Heat in the coarfe mechanic way, by friction with a folid body ; or that fo confiderable a change was made on the ftrUiSture of the minute parts of bodies, as is made in this procefs, without producing Heat at the fame time ; and fince in fermentation, putrefaction, &c. the Heat is not pre- tended to be owing to the veflels containing the changed fub- ject, but to what happens to its minute parts, in undergoing the change, it feems, on the whole,, an unphiljfophic par- tiality for mechanics to maintain, that our juices have all their Heat communicated to them from the folids, and acquire it by rubbing with the veflels. See Medic. Ell". Edinb. vol. 5. art. 77. Abridg. Vol. 1. p. 222. feq.
A late author thinks the Heat of animals explicable from the phofphorus and air they contain, Phofphorus exifts, at leaft in a dormant ftate, in animal fluids ; and it is alio known that they ail contain air j it is therefore only neceflary to bring the phofphoreal and aereal particles into contact, and Heat mult of confequence be generated ; and were it not for the quan- tity of aqueous humours in animals, fatal accenfions would frequently happen. Dr. Mortimer ap. Phil. Tranf. N° 476. feet. 20. See the article Phosphorus.
HEATH, Erica, in botany. See the article Erica.
Heath-/;m, in zoology, a common Englifh name for the urogallus, or tetrao minor, called alfo the groufe. See the article Grouse.
Heath-ot/j, CoraUoides, in botany, the name of a genus of the mofl'es ; the characters of which are thefe : They are compofed of ftalks often branched in the manner of corals, and compofed of parts of a different figure and appearance, not fimple and uniform as the byfli and confervas. On the fummits of the branches there grow a fort of flefhy tubercles, which Micheli calls the receptacles of flowers ; and the little atoms v/hich are ken adhering to the different parts of the ftalks, he calls the feeds. Dillenius is rather for thinking them the farina ; and the tubercles, either the capfules of feeds, or the young plants, ready to fall off from the parent item, and fhoot for themfelves like the bulbs of the dentaria, biftort, and the like. However this be, thefe are parts too minute to found generical diftinctions on, thefe may be better deduced fron* a groffer dofifideration of the ftalk, and the figure of the tubercles. Thefe have no rim or margin, and are ufually lar- ger in the lefs branched kinds, and fmaller in the more ramofe. This being a very numerous genus of moffes, it is divided into feveral orders : 1. The fungiform 2. The cup-like. 3. The ramofe, or corniculate ones. DiUen. Hift. Mufc. p. 76. The fungiform CoraUoides, are neither hollow nor branched. Of thefe there are only five known fpecies : 1. The flefli- coloured fungiform CoraUoides ; this has a wide cruftaceous and granulated bafe, of a greenifti or greyilh colour ; on this there firft appear feflile tubercles of the bignefs of a pin's head, and of a pale flefh-colour. Thefe afterwards rife up, and are fupported on fleuder pedicles, and grow to the fize of cori- ander feeds. It has been called by moft authors a fungus, by fome a lichen, and by fome a lichenoides. It is found in England and other places. 2. The brown mufhroom-like CoraUoides. This has a dufky foliaceous bafis, from which it
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rife in form of {mail oblong ftalks, which widen into' a fort ct tubercles at the ends. This is found on Hampftead Heath and in other places. 3. The fmall black pin-l.ke tree Co- raUoides. This has very little cruftaceous matter at the bot- tom, and its heads arc- of the fize of mufiard-feeds, fupported on fmall black ftalks, the whole not unaptly refembling pins with their points fluck in the wood. 4. The pale fmall frone p,n-l,ke CoraUoides ; This has a large cruftaceous bot- tom, and its fungiform heads are very fmall, and placed upon very fhort ftalks. 5. The pale fkih-coloured lhort-ftemmed fungiform CoraUoides ; This has been often found on the hoofs of trortes half rotted with the weather, and has been ufually called a fungus by authors. See Tab. 2. of Botany, N° .5 I he CoraUoides of the fecond order, or the Cli'-nnlli:, as they are ufually called, are tubulofc, ufually not branched, and often fingle, often proliferous.
Of thefe there are fome which have more regular and perfeS cups, and others which have them lefs perfect. Of the more perfect kind are the following fpecies. t . The common Cuf CoraUoides, or Cup-mofs. 2. The fcarlet-headed Cup-mofs. 1 his is lefs common than the former, and is adorned with beautiful fcarlet tubercles. 3. The Cup mofs, with indented edges. This is ufually taller and flenderer (hail the common kind, and is frequent on ditch-banks, &c. 4. TBe Cup-mofs, with radiated edges. The rims of the cups in this are beauti- fully foliated. 5. The fmall rattle leav'd Bup-mfs. The cups of this are formed like the mouth of a trumpet, and grow out of a large and beautifully divided leaf, creeping upon the ground ; the cups are fmall. 6. The fhort-footcd Cup CoraUoides. The leaves of this fpecies creep on the ground, and are green on the upper fide, and white underneath S the cups which arife from thefe are fmall and brownilh within 7 T. he elks-horn-leav'd Cup CoraUoides. The leaves of this are large, and ftand fomewhat ercft, and have fegmeBtk iikc an elk s horn ; they are fmooth, hard, and cartilaginous ; the cups are fmall, and rife from every part of thefe ; they are hut lightly hollowed, and a little cremated at the edge. 8. The' branched and indented Cup-mofs. This is taller and flenderer than the other Cup-moji-s, and the pedicles of the cups are fmooth and very {lender.
Of the Cup-mffes, with lefs perfeft cups, the following are the known fpecies: 1. The ftewer CoraUoides. Tins is fcarce at all branched, and its cups are not eafily diftinguiih'd." It is commonly called horned Mofs ; the cups have tu- bercles, and are fttuated near the bottom of the.ftalks ; it is very common on heaths. 2. The thighbone Cup CoraUoides. The tubercles on th>s are large and brown, cover the whole extremity of the ftalk, fo that the cup is fcarce difcernible. 3. The horned Cup CoraUoides. This grows to two inches high, and is fometimes branched ; it is of a greenifti white colour, and is hollowed into a cup at the end ofeach. 4. The branched cornucopia; Cup-mofs. This is hoary on the fur- face, and the cups are crufted at the edges. 5 , The clurrffy indented Cup CoraUoides. This is hoary on the furface, a'hd of the thicknefs of a goofe quill, and of a greyifh green colour. 6. The fcarlet headed branched Cup-mofs. 7. The brown- headed lefs branched Cup-mofs. Thefe are but very lightly pixidated, and the firft of the two fcarce diftinguifhabfy fo Dillon, Hift. Mufc. p. 100.
Of the third order of the' CoraUoides, or tliofe which are' branched, and appear like fmall drubs, with their tops bent, and divided into numerous fine ramifications. The following are the known fpecies : 1. The great foft perforated Coral, hides. This is very common on Heaths, and grows to three" or four inches high. 2. The fmall, foft, open CoraUoides. This is whiter and more branched than the former. 3. The elegant fine cut CoraUoides. The joints of this are hollowed like a faucer, and nicely foliated. It is a native of the Ame- rican Iflands. 4, The little, crifp, imperforated CoraUoides. Ibis is found in Virginia. 5. The prickly, diftorted Coral- loiiles. This fpteads varioufiy and irregularly on the ground. 6. The lefs branched horned CoraUoides. This is common in woods among other Moffes. 7. The more branched Co- raUoides, with fhorter ramifications. This is frequently found about the roots of trees. 8. The fmall, brittle, madrepora- like CoraUoides. This fcarce exceeds half an inch in height. 9. The common white mountain CoraUoides, called ren-deer- mofs. This is every where common with us on Heaths, and is what the ren-deer feed upon in Lapland. 10. The com- mon mountain CoraUoides, with brown tips. This is com- pofed of flenderer branches than the former, and the extremi- ties of all of them are tipped with a reddifh brown, whereas the others are white throughout. 11. The brown folid prickly CoraUoides. This is a very elegant fpecies ; it rarely " exceeds an inch in height, and is very much branched. 12. The black lace CoraUoides. This alfo is a very elegant fpe- cies, it rarely exceeds half an inch in height, but fpreads very wide ; it has no thick ftalk, but is compofed of numerous fine ones, fo interwoven as to refemble lace. 13. The crifp warty alpine CoraUoides. This grows to rocks and ftones with a woody bafe, in the manner of the fea focus's, and rifes varioufiy branched to an inch or two in height. 14. The alpine coralline-like CoraUoides. This is called, by fome,
mountain
