473 



BUTTRESS. 



BUTYL. 



474, 



shire; Redgrave, Suffolk; Gadsby, Leicestershire ; and at the east end 

 of Walsingham Priory. This last is almost in the perpendicular style, 

 which immediately followed the decorated. 



Third Pointed or Perpendicular English buttresses vary chiefly from 

 those of the style which preceded them in that they are generally higher, 



Perpendicular English Buttress. 

 Woolpit, Suffolk. 



Decorated English Buttress. 

 Waltham Cross. 



project more in proportion to their width, are of more numerous stages, 

 are commonly panelled, .and hare the edges left sharp instead of, as 

 hitherto, being chamfered. On the whole, however, they display less 

 freedom of design. The heads of buttresses in the earlier part of this 

 period are triangular, but are not acute-angled, as in those of the 

 preceding century, and have crockets of very ornate character. In 

 later examples, buttresses have sometimes flat terminations, which 

 serve a pedestals for figures, as at King's College chapel, Cambridge ; 

 St. George's, Windsor ; Beauchamp chapel, Warwick, and the Lady 

 Chapel at Peterborough. Flying buttresses of extraordinary dimensions 

 and elaborateness occur in French Gothic churches, as at Amiens, 

 Rheims, St. Ouen, Ac. Octagonal turrets are sometimes used as but- 

 tressed, as in Henry VII.'s chapel at Westminster, from which spring 



the flying buttresses. The most superb of this kind ever executed in 

 this country belong to this edifice. 



Flying Buttress, from Henry VII.'s Chapel, Westminster. 



(Ample details respecting buttresses will be found in Brandon's 

 ' Analysis of Gothic Architecture ; ' Parker's ' Glossary ; ' the ' Dictionary 

 of the Architectural Publication Society;' and the works of Britton, 

 Bloxam, Pugin, Paley, Chapuy, De Caumont, Le Due, &c.) 



BUTYL (C 8 H 9 ), Valyl, tetryl. The radical butyl was first discovered 

 by Kolbe, among the substances produced by the electrolysis of 

 valerianate of potash. Its formation is hence quite analogous to that 

 of the radical methyl (C 2 H 3 ), from acetate of potash. [METHYL.] It 

 has also been obtained by Wurtz, by the action of potassium upon 

 iodide of butyl. When pure, it is a limpid oil with an agreeable 

 etherial odour, of the sp. gr. 0'694. It boils at 226 Fahr., and distils 

 without alteration. It is only attacked with difficulty by oxidising 

 agents. By the action of chlorine substitution products are formed. 



Butyl is contained in a numerous fa'mily of organic substances, of 

 which the following are the most important : 



Butylic alcohol I "TT" f 2 ). This substance is a member of the 



series of homologous alcohols of which ordinary alcohol is the type, 

 and the general formula for which is CnHn+ a 2 . It was discovered 

 by Wurtz as a constituent in varying quantities in certain crude 

 alcohols resulting from the fermentation of beetroot molasses. To 

 obtain it, the crude alcohol is submitted to fractional distillation, and 

 the distillate between 221 Fahr. and 239 Fahr. separately collected. 

 This is then treated with potash and distilled, the distillate dehydrated 

 over caustic lime, then re-distilled, and the product thus obtained 

 rectified. What now passes over between 226 Fahr. and 230 Fahr. is 

 pure butylic alcohol. 



It is a colourless, highly-refracting liquid, with an odour resembling 

 amylic alcohol, but more vinous. It has the sp. gr. 0'803, and it boils 

 at 228 Fahr. It is more soluble in water than amylic alcohol. 



Its formation from sugar may be thus expressed 



2(C 12 H 1S 14 ) = 2(C 8 n, O s ) + SCO, + 4 HO 



Grape Sugar. 



Butylic alcohol is homologous with common alcohol, and in its 

 chemical relations and physical properties it presents, with regard to 

 that substance, all the regular gradation of properties which charac- 

 terises a true homologue, and accordingly we view it as containing the 

 radical liUyl, C 8 H , of which it is the hydrated oxide (C,H,0,HO). 

 [ALCOHOLS.] Like vinic alcohol it undergoes a series of changes 

 under the influence of various reagents, and the substances produced 

 bear the most perfect resemblance to those formed under the same 

 circumstances from alcohol. It will not therefore be necessary to do 

 more than briefly mention them. 



When potassium acts upon butylic alcohol, hydrogen is liberated, 

 and a crystalline product is obtained, bMylate of potash (C 8 H B 0,KO). 

 By the action of soda-lime at a high temperature, hydrogen is liberated, 

 and an alkaline butyrate is formed. Pentachloride of phosphorus 

 attacks butylic alcohol energetically, and forms Moride of butyl 

 (C 8 H.C1), a colourless liquid of an etherial odour, which boils at about 

 160 Fahr. 



C 8 H, 0,, 



PC1 5 = 



Butylic Pentachloride 

 Alcohol, of Phosphorus. 



r C 8 H,C1 + P0 8 C1, 



Chloride Oxychloride 

 of Butyle. of Phosphorus. 



This compound is also formed when butylic alcohol is treated with 



