Renseignements généraux

Nº de série

S/O

Nº de partie

1

Nombre total de parties

1

Ou

S/O

Brevets

S/O

Description générale

wood, metal, synthetic, string and mercury materials of construction.

Dimensions

Remarque : Cette information reflète la taille générale pour l’entreposage et ne représente pas nécessairement les véritables dimensions de l’objet.

Longueur

17,8 cm

Largeur

10,8 cm

Hauteur

36,0 cm

Épaisseur

S/O

Poids

S/O

Diamètre

S/O

Volume

S/O

Lexique

Groupe

Exploitation forestière

Catégorie

Lutte contre d'incendie

Sous-catégorie

S/O

Fabricant

Ou

Great Lakes

Pays

Canada

État/province

Ontario

Ville

Sault Ste. Marie

Contexte

Pays

Canada

État/province

Ontario

Période

Used in late 1970s.

Canada

This device was designed by Canadian Forest Service, Great Lakes Forestry Centre, and used in experimental fires in Ontario.

Fonction

To measure the rate of spread of fire in experimental burning plots.

Technique

This device allows the used to mechanically calculate the rate of spread of fire in experimental burning plots. the rate is calculated by simply dividing the spread distance in metres by the period of observation in minutes. Separate estimates of rate of spread are made for each fuel type or topographic unit in plots. Rate of spread is often estimated by timing the movement of the fire front between two points (ie. rocks or snags], of known distance. Where faster moving fires are anticipated (>10m/min), a grid system is set up on the site before the burn, and a stopwatch is used to determine how long it takes the fire to cover a predetermined distance. This device eliminates the need to use a stopwatch. Instead, the devices are buried in ground on a grid in a plot. When fire arrives at a location, it burns the string extending from the box, which drops the mercury switch inside to activate the encased clock. After the fire, the devices are retrieved and the time of arrival of fire recorded from the clock. An average spread rate of fire is determined based on plot times. (ref. 1)

Notes sur la région

Inconnu

Détails

Marques

"19" handwritten in black marker on box (casing) top.

Manque

None.

Fini

Unfinished wooden box has plexiglass window in one end; metal hinge permits access to switch compartment. Box top fitted with string and metal hardware. Metal and synthetic clock; metal, synthetic, string and mercury components used in construction of switch.

Décoration

S/O