Thank you so much for coming to Alberta and sharing that wonderful clinic with us!
Before we dispersed, I forgot to get the recipe for preserving the bones. I was quite thrilled when I went out to the back corner of the pasture and managed to find quite a significant amount of one of the horses out there. The snow and muskeg have made it tricky to find all pieces - that's if they are all there - but a good portion were present.
Melyssa, you'll have a great opportunity for learning as you figure out how to fit together all the pieces that you did manage to recover. It's quite normal for small parts to be lost unless extraordinary precautions are taken, or unless the bones are prepared in a laboratory setting.
As I suggested, try to get up to Drumheller and take notes off the skeletons there. See if they don't also have a "learning center" open to the public, where there are skeletal bones (not necessarily of horse, but still very helpful) that you can handle. Sometimes there are even knowledgeable staff on hand at such places who can guide you in "articulation".
As to the preservative formula:
You will need: Small container (1 pint, approximately, or as small a quantity as you can buy) of spar varnish. Spar varnish is a 100% organic product, made from tree sap; DO NOT use anything containing petroleum distillates or acrylics.
Large container (gallon size) of gum turpentine. Again, gum turpentine is a 100% organic product, made from tree resins; DO N OT use anything containing petroleum distillates or acrylics.
2 disposable aluminum turkey roasting pans, approx. 10-14 inches long X 8-10 inches wide by 4" deep.
1 plastic bulb-and-tube type turkey baster.
In one of the turkey roasting pans, mix: 1/4 cup spar varnish with 4 cups turpentine. Mix by stirring with bulb and tube. This makes a VERY THIN mixture. The preservative is intended to penetrate rather than coat the bones.
Select a bone and put it in the empty turkey roasting pan. Then use the mix to "baste" it well, squirting preservative into every orifice. You'll probably want to wear disposable latex gloves; hold the bone by one end, turn it as you baste it.
You'll need a quantity of newspaper and some shelves. After basting, place bones on newspaper on shelves. Important: set bones on their most "prickly" edges; do not set flat surfaces down flat. This because the preservative is going to drain off onto the newspaper and make pools around whatever part of the bone it may be resting on. These pools will harden as rims which you later will have to carve off by light use of a knife. Much easier to trim the rims off of small pointy areas than big flat ones!
Also note: DO ALL OF THIS OUTSIDE. The turpentine gives off huge amounts of fumes that aren't particularly good to breathe, and which are also flammable/explosive. So be outdoors while you work, and have your drying racks outdoors too.
DO NOT BEGIN this project if there is any moisture in the bones -- preservative on top of wet bone makes a gunky mess.
After basting dry bones and setting them on rack to dry, it will take a couple of weeks for the preservative to set up and the fumes to dissipate. After carving off any rims, store preserved bones in "Roughneck" plastic tubs or other suitable container.
Have fun with this -- I love it that several people from our class seem to know where to find horse skeletons on hilltops. Go collecting! Much easier for us if Mother Nature does most of the skeleton preparation. Cheers -- Dr. Deb