Saturday, October 8, 2016

How animal glue is made...

In the "Natural History" of Pliny the Elder, book 11 chapter 94, Pliny says that "From the hides of oxen, and that of the bull more especially, glue is extracted by boiling." The entirety of book 16 chapter 83 is on "Woods united with glue."
From http://swingleydev.com/ot/get/237392/thread/


XVIII. Glue made from Hide and Hartshorn
When this has been carefully dried, take some cuttings of the same hide similarly dried and cut them up in small pieces. Take some hartshorn and, with a smith’s hammer, break it up into small pieces on an anvil. Half fill a new pot with them and fill it up with water. Then heat until a third part of the water has evaporated, but taking care not to let it boil. You test it in this way: moisten your fingers in this water, and if, when they are cool, they stick together, the glue is good; but if not, heat it until they do stick together. Then pour this glue into a clean vessel, and again fill the pot with water and heat as before. Do this four times.

Oil of hartshorn is a crude animal oil obtained from the destructive distillation of the deers' bones or horns. https://en.wikipedia.org/wiki/Hartshorn


Theophilus (c.1122) "On Divers Arts" Translated from Latin by C.R. Dodwell to The Various Arts; published by Thomas Nelson and Sons, Ltd. in 1961.

CHAPTER CVIIII HOW GOAT GLUE IS MADE, AND HOW IT IS TEMPERED; AND HOW MANY PURPOSES IT WILL SERVE.
And there is a glue which is known as leaf glue; this is made of clippings of a goat’s muzzles, feet, sinews, and many clippings of skins. This glue is made in March or January, during those strong frosts or winds; and it is boiled with clear water until it is reduced to less than half. Then put it into certain flat dishes, like jelly molds or basins, straining it thoroughly, Let is tand overnight. Then, in the morning, cut it with a knife into slices like bread; put it on a mat to dry in the wind, out of the sunlight; and an ideal glue will result. This glue is used by painters, by saddlers, and by ever so many masters, as I shall show you later on. And it is good glue for wood, and for many things. […]

Cennini, Cennino d’Andrea (lived c. 1360–1427) "Il Libro Dell’Arte" The Craftsman’s Handbook, translated by Daniel V. Thompson, Jr. 1933 Dover Publications, NY (no publishing date, but after 1960).


186. How to make glue from the skin of an ox or a cote.
—Take the skin of an ox or a cow, as thick as you can find it, which has already been tanned for shoes, and put it in a jar and pour water upon it, and make it boil over the fire from daybreak on a summer's day until nearly the third hour of the day, pouring water into it when necessary, or, when it is much diminished, pour off the water, which has boiled so long, and pour in clean water, and make it boil again until the sixth hour. Then pour off this water, which will be  nearly all evaporated, and again pour clean water into the jar over the  same leather, and do  not  renew it  more than once or  twice more. And take great care not  to  let  it  boil over, and then, having boiled it  down to  one-third, pour it  into  a  vase, and  leave it  to cool  all  that  day  and night. In  the  morning of the  next day if  it  is  coagulated in  the  vase, put  your finger upon it.  If  any part of  it  remains sticking to  your finger, you  may know that  it is  not  good, and  may throw it  away as  refuse. Afterwards fill up  the  jar  with water as  before, in  order to  boil it  with the leather ;  and  you must not  fill  it  up  any  more, but  take  all possible care not  to  let  it  boil  over. You will  know when it  is good by  (after you  have boiled it  sufficiently and let  it  cool) putting your finger upon it  as  before, to  see  whether it  is  hard  ; and the  harder you  find  it,  the  better you  may know it  to  be.

Afterwards putting a  small portion of  it  into  an  earthen vase, set  it  on  the  coals and  make it  rather warm. Then, removing the  vase from the  fire, keep it  at  a  moderate heat over a  slow fire  made of  a  few  pieces of  charcoal, lest it  should be  con S.  AUDEMAR DE  COLORIBUS FACIENDIS. 149 grossiores vero quae per  pannum transpire non  poterunt iterum in  ipso  mortario mitte et  molle sicut antea feceras. Et   3emper minutiorem partem per  pannum transpire facias sicut dictum  est  et  repone cum similibus minutiis et  sic  postquam in  mundissi- mum pulverem redegeris stannum protrahe super pergamenum et  super pannum flores et  imagines et  quodcumque opus volu- cris. Et  in  ipso  opera per  loca  que  de  aurare vel  argenteare voles, pones v 

Mrs Merriefield (1849) ORIGINAL TREATISES, DATING FROM THE XIIth TO XVIIIth CENTURIES in the ARTS OF PAINTING William Clowes & Sons. London

Free download at:
https://books.google.com/books?id=2xgGAAAAQAAJ&printsec=frontcover&dq=ORIGINAL+TREATISES,+DATING+FROM+THE+XIIth+TO+XVIIIth+CENTURIES+in+the+ARTS+OF+PAINTING&hl=en&sa=X&ved=0ahUKEwjy28OGucvPAhVCKCYKHTqKDGAQ6AEIHjAA#v=onepage&q=ORIGINAL%20TREATISES%2C%20DATING%20FROM%20THE%20XIIth%20TO%20XVIIIth%20CENTURIES%20in%20the%20ARTS%20OF%20PAINTING&f=false

A neat article on period glue as it pertains to modern wood working:
http://www.oldbrownglue.com/images/articles/Why_not_period_glue.pdf

A class handout with lots of background information on different period glues  :
http://www.rocks4brains.com/glue.pdf

1 comment:

  1. Great post. Thank you for sharing interesting information about Animal Glue. Keep up your posting.

    ReplyDelete