Back in June I wasn't exactly accurate when I blogged about A unique historic government fonds LAC refused.
I recently discovered that LAC does hold some of the earliest meteorological registers in RG93 1984-85/002. Some are bound register books, some bundles of register sheets, one week per page. What's more they provide more detailed information than available online from the Meteorological Service of Canada's past weather and climate databases.
This example is a page from the Ottawa reporting station for the week ending 2 January 1875.
For each day there are observations reported in the morning, late afternoon and late evening. The barometric pressure, air temperature, humidity, wind sped and direction, weather description, cloud report, times of rain and snowfall beginning and ending, and rain and snow accumulation, are all recorded in imperial units. The summary reports maximum and minimum temperature and the amount of rain and snow.
These registers could be useful if you're looking to add colour to a description of a family event, such as a wedding,