Finished syrup is 66% sugar. This is when the syrup is 7.1 degrees F above the boiling point of water or when the hydrometer reads 66 degrees Brix. A candy thermometer can be mounted in the finishing unit with a clap or piece of wire. The temperature where the sap begins to boil is roughly the boiling point of water. The boiling point of water varies with barometric pressure, so it can be different every day. When the syrup is at the correct density, transfer the syrup to heat sterilized bottles or canning jars. Filtration of the syrup is a good idea at this point. As the sap is cooked, a substance called sugarsand precipitates. While it will precipitate to the bottom of the jar in storage, the sugarsand can be filtered for a better syrup presentation (imagine pouring out some gritty sugarsand onto a pancake). If the product is to be sold, filtration is essential. The syrup has be at least 180 degrees F when canning to remain untainted in storage. Remember to use hot bottles if possible, as the temperature of the bottles affects the temperature of they syrup. Cap the bottle and turn then over to sterize the lids.