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5. Take of maftich half* an ounce, of whitefrankincenfe a quarter of an ounce, of lauda-rach half an ounce, of benzoin half an ounce,and diflblve the ingredients in a pint of highlyretfified alcohol: a colourlefs varnifh is thusformed, which is employed for defending thefdvering of clock-faces, of barometer feales,and other fimilar articles, from the ahfion ofthe air.

6. Take of fandarach 6 ounces, of elemi 4ounces, of anime 1 ounce ; pound the wholetogether, and then add 4 ounces of coarfelypulverized glafs: infufe the mixture in a quartof rehfified alcohol, and add at intervals as thefolution goes on half an ounce of camphor.The refult is a very good colourlefs varnifh forboxes of papier mache and fimilar articles.

7. A fimilar varnifh to the above but fome-what coarfer, is compofed of white frankincenfe6 ounces, anime and elemi of each two ounces,pounded glafs 4 ounces, and a quart of alcohol.

(1. 2. EJfential Oil Varnijhes.

The high price of moll of the eflential oils isfuch as to preclude the varnilher from the ufeof them; oil of lavender is occafionally em-ployed, but the ufual menftruum is oil of tur-pentine. The purity of this latter fluid is ofthe utmoft importance: that which is com-monly fold at the oil and colour fhops, thoughfufficiently pure for oil painting, will veryrarely anfwer the purpofe of the varnifher, whoif he wilhes to fave himfelf from much mortifi-ca ion and difappointment will apply for thisarticle to Apothecaries’ Hall, London , whereit is conftantly to be procured in the utmoftpurity.

Varnifhes with oil of turpentine and therefins are fomewhat fofter but eonfiderablytougher than thofe prepared with alcohol ;hence they are not fo liable to crack and fcaleoff*. They are principally ufed for varnifhingoil paintings, for mixing up colours with, andfor lacquering. A compofition applicable tothe firft of thefe purpofes is the following.

8. Take of pure and wafhed maftich 12ounces, and of pounded glafs 5 ounces, infufethe mixture in a quart of pure oil of turpentine,-adding at intervals half an ounce of camphor infmall pieces; when the maftich is diflolvedadd to the warmed fluid an ounce and a halfof clear turpentine previoufly melted, and ftirthe mixture together till it is thoroughly incor-porated.

Several of the copal varnifhes may be alfoarranged under this feftion, efpecially thofethat are beft fitted for varnifhing articles of

wood and pafteboard. Several of thefe havebeen already deferibed under the article Copal ,to which we refer the yeader. To thofe rmybe added the following very Ample and veryefficacious one.

9. Take from 3 to 4 ounces of copal thathas previoufly been liquefied in as gentle a heatas poffible, and 20 ounce meafures of thepureft oil of turpentine; put this latter in amattrafs fet in boiling water, and add the pul-verized copal in fmall quantities at a time, inproportion as it is diflolved. If the materialsare good, and the procefs well conducted,fomewhat more than 3 ounces of copal will betaken up, and the liquid will be a little cloudy :by Handing for a few days it will become clear,and fhould then be ftrained through cotton.This is a thick varnifh, and will generallyrequire to be diluted with a little warm oil ofturpentine before it can be ufed: it forms avery hard and durable glazing, which will dryin fummer in the fpace of two or three days, orin a lefs time if put into a warm ftove.

§• 3. Fat Oil Varnijhes.

Thefe are tougher and lefs liable to crackthan the preceding, and by expofure to a properdegree .of heat may be made to acquire a verygreat hardnefs : they are however very long indrying without the afliftance of a ftove, andgive out an extremely difagreeable odour duringdrying: they are alfo for the moft part highcoloured, and are therefore feldom ufed bythemfelves, but mixed up with fome opakebody colour. The materials employed in thecompofition of thefe varnilhes, with the excep-tion of mere colouring fubftances, are the fol-lowing, copal, amber, afphaltum, drying oil,and oil of turpentine.

The moft colourlefs of the fat varnifhes isthus prepared.

10. Take of copal liquefied, according toTingry’s method, and finely pulverized, 4ounces, of drying linfeed oil and oil of turpen-tine, each 10 ounces; put the whole into amattrafs, and apply a very gentle heat till thecopal is diflolved : this being done, let the var-nilh Hand for a few days to clear, and after-wards ftrain it through cotton. This forms afolid and nearly colourlefs glazing, and drieseafily at the common temperature.

11. Take of picked copal 16 ounces, andmelt it in a clean iron pot with as gentle a heatas poffible, when itsfufion is compleat, pour in3 ounces of drying linfeed oil boiling hot, andincorporate the ingredients by ftirring; thenremoye it from the fire, and while it is yet