4 grains.

The obolo is half a Spanish scruple; 3 silicua make 1 obolo, and 4 grains a silicua.

A loth, in Germany, Poland, etc., is half an ounce.

The commercial pound in several countries differs from the pharmaceutical. The civil pound of Bavaria and mark of Vienna are each about 19 3/4 avoirdupois ounces. That of Holland is the French kilogramme, or 12 grains more than 2 lbs., 3 1/4 oz. avoirdupois. The mark is half a kilogramme. The Coburg commercial pound is nearly 18 oz. avoirdupois.

3. - Foreign Measures.

The Austrian mass or keanne is equal to 1.415015 litres, or 2 1/2 imperial pints, within 40 minims.

The kanna of Sweden = nearly 2.62 litres, or about 4 pints 12 ounces imperial.

Russian pound of water = 25.019 English cubic inches.

The pott (half kanne) of Denmark = 09653 litre.

The arroba of Spain = 16.073 litres.

The almude of Portugal = 16.451 litres.

The Prussian quart = 1.145 litre, or 1 qt. fl. dr. imp.

The barile of Naples = 43.6216 litres; of Rome, 58.5416 litres; of Tuscany, 45.584 litres.

The wedro of Russia (10 stof or 30 Russian pounds) = 12.29 litres, or 21 pints 12 oz. 12 1/2 drs, imperial.

The mass of Wurtemburg = 1.537 litre, or about 3 pints 14 3/4 oz. imperial.

Comparison of Thermometric Scales.

To convert the degrees of Centigrade into those of Fahrenheit, multiply by 9, divide by 5, and add 32.

To convert degrees of Centigrade into those of Reaumur, multiply by 4 and divide by 5.

To convert degrees of Fahrenheit into those of Centrigrade deduct 32, multiply by 5, and divide by 9.

To convert degrees of Fahrenheit into those of Reaumur, deduct 32, divide by 9, and multiply by 4.

To convert degrees of Reaumur into those of Centigrade, multiply by 5 and divide by 4.

To convert degrees of Reaumur into those of Fahrenheit, multiply by 9, divide by 4, and add 32.

In De Lisle's thermometer, used in Russia, the graduation begins at boiling-point, which is marked Zero, and the freezing-point is 150.