762
INUlJSTEI.4 L AVD E.VGI.VKKFiI.VG CHEMISTRY
water hatli, goes through the range from 100' to 104" C'. and back to 100" C., a second mol of water is lost. I n the rapid heating process approximately tlie satire losses of water were noted, but tlie soluhility in acetone was mucli less.
Vol. 23, No. 7
iindissolved state, but they have the advantage of giving darker stains for the sanie concentrations in acetone solution. Costs
It was found a t Armiston that the cost US pure crystallistd xylose is riiuch greater t,haii that of an impure product in All the products except tlie granular one at 4 3 ~ 5 0 "C. cake form, the purification and crystallization being the dissolve to some extent in acetone. The resin made by 1argFst items of expense as to time, apparatus, and expert holdiiig t.he temperature a t 7580' C. gives the best and control. The earlier experiments on tlrc xylose-aniline clcarest solution for varnirli purposes. Acetone is t h e on1y resill were made with piirified xylose and laboratory quality coiriniuii organic iolvnit which will dissolve it. Tlie ac~tatonc aiiiliiit:. Later work has shown that even better results, adutioii f l u ~ sreadily frim the briisli, lias good covering nt a Iowr price, can he had with aniline oil and irripiirc power, mid drips in aliout 30 xiiinutes. Wlien applicd to rake x>-llise still containing gums and coloring inat,trr. While no cost sluiets are available for the in>pure cake pinc wood it ranges from cherry, tlirougli mahogany, to dark oak, according to the c~incc~ntration OS blie solution. Tlie xylosr cniployed, it is estimatcd to he about 2 crnts pcr finished n m k is of a satiafartriry luster and is proof to hot pou~icl. The finislicd varnish contains from 2 to 5 pounds water, alkalies, arid acids except nitrir, nhicli gives a redder OS tlie resin to tlie gallon, according to the drptli of color t,iiit T>-ithoiitremoving the raruish. In making the variiisli required for onc coat. The hcaviest varnish would tlierefore solution it wns found advantageous to dissolve the resin require about 2 p(iiiiids of aiiiline tu the gallon. The r a x shortly after it was ~nxdeor to protect it from the air. If niateriala for this varnish, using the unpurified xylose, sliould left uiidiasulved in criutact with air, it does not dissolve not cost more than abr)ut $1.00 per gallon. The equipment so well later, t i m e is an undissolved residue of the r t t h , Sor niaiiufact,ure and the procedure are very simple. and the finished rvork has le= luster. Tlie resins i i i a d e Literature Cited by the slow process at temperatures higher than 80" C. are m u c l i niore susceptible to change hy air exposure, in the [ I , schrriber, la". Production of Varnish
The Crystal Form of Paraffin Hydrocarbons' G. D. Craves E. 1. uu P o ~ r UB N s r u a n s A N D C o ~ m i u WLLIINCTUN, . Dai.
Clif?: paraffin liydroearboiis frorii C,& to C,H, as isolated from petroleurn waxes crystallize in platcs quite distiiict. froiii the characteristic needles formed by sample$ less carefully purified (1). Four photomicrographs are presented here showiur that synthetic normal paraffin carbons containing 22, 23, 30, and 40 carboil atom li form piatitlike crystals apparently ideiiticai with those petrolciim waxes. The Ilydrocarbon was prepared by the electrolysis of lauric acid. It,s 1 ng point was 44.3' C. Tlie liydnrcarbon ( X X i mas prepared iby catalytic hydrogeuation of laorone. I t Ineltcd at 4i.8" C. The vriter is indebted to E. E. Reid and F. 0. t kerille, wlio Surnished these saiiiples Received April 30, 1031. Cuntiibutioii 50 lrom the Bxpriimritial Station ol E. I du Poni de Seiiioiirr m d C o . t
and who will descrihe them in a later publicatkm 7'he liyrlrocarbons C&x and CoHvz were synthesized at this Iahoratory by the action of sodium on decamethylene bromide. They have already heen described (?). I n each case the method of synthesis leaves no doubt as to the strueturc of the resulting compound. The photomicrographs were h k e n osing polarized light as has been described prerioualy ( I ) . Mqpifications are X 80. The writer is indebted to H. B. l)e\'ore for assistaiiee in obtaining the photomicrograplis. Literature Cited ( 1 ) liuchler iuid Grrves, IN". Evo. Cnrx.. IS, 718 (19271. (2, Cnrotherr. Hill, Kirby, m d Jacobson, J. .im.Cicm. .Yoc., 62, 5270
(1930).
