516 REPORTS ON THE STATE OF SCIENCE, 



above it. Show ' convection ' currents in a beaker of water when heated. Refer 

 to ocean currents and the circulation of hot water in a house system. 



Construct a spirit thermometer, and graduate it to show temperatures of 

 melting ice (0° C. or 3:2° F.), of a living room (about, 60° F.), of the human body 

 (98° F.\ of a hot bath (not higher than 100° F.). The Centigrade and Fahrenheit 

 methods of graduating the thermometer. 



The mercury thermometer; the boiling-point and freezing-point of water. 

 The thermometer an instrument to measure temperature or hotness. First notions 

 of heat as disiinct from temperature. The measurement of amount of heat 

 depends upon at least two quantities — the amount of substance heated and the 

 temperature to which it is heated. 



The doctor's thermometer for measuring the temperature of the human body ; 

 constructed so that it still indicates the body temperature when removed from the 

 mouth of the patient; method of using and cleansing; temperature of body in 

 sickness and in health. 



Ice floats on water ; water when frozen must therefore expand ; make a 

 mixture of spirit and water in which ice remains suspended ; find the weight of 

 1 c.c. of the mixture, and hence wnight of 1 c.c. of ice. Refer to bursting of 

 water-pipes by ice, and explain why ice is always found at the surface, and the 

 importance of this fact. 



Air expands much more readily than solids or liquids when heated. Heat a 

 Florence flask in hot water, and find how much 1 c.c. of air expands when made 

 1° C. hotter. Weigh a flask first full of cold air, then of hot air. Hot air is 

 lighter than cold air. Show the air currents above a flame in a hot room and up 

 a chimney. Refer to winds, draughts. Show eflfect of a strong draught on the 

 burning of a fire. 



Burniutr and breathing both make the air hot and poisonous, and unfit to be 

 breathed again. Natural and artificial means of ventilating a room. Necessity 

 for fre.sh air and sunlight. 



Determination of melting-points of butter, paraffin wax, or beeswax, and 

 boiling-point of water, brine, spirit. 



Evaporation ur drying — the slow change of liquid into gas or vapour. Evi- 

 dence thnt heat is absorbed during drying ; clothes dry quickly on a windy day : 

 good and bad drying days ; compare with barometer readings. Presence "of 

 water vapour in the air. Evaporation of perspiration on the skin, and its cooling 

 effect in hot weather. 



Textile fabrics (especially woollens) have power of absorbing water vapour 

 from the air. Weigh roll of dry flannel, and again weigh after exposure to air for 

 a couple of days. Make daily weighings of a bag of seaweed, also observations of 

 thermometer, barometer, and the kind of day. 



Condensation of moisture (water vapour) in the atmosphere ; formation of 

 cloud, dew, and frost. The heating power of steam. Boil water by passinir steam 

 into it. ^ Find roughly what weight of steam will boil a given weight of water. 



Distinction between dissolving and melting. Determination of soluble, 

 insoluble, and partially soluble substances used in the household. The amount of 

 .solid matter contained in common beverages is very small, and the food value 

 is not therefore great. Repeat experiment with milk. Foods must be rendered 

 soluble before they can pass into the blood stream and so nourish the body. 



Distillation — a double process of evaporation and condensation. Liquids can 

 be distilled, but solid substances dissolved in water do not usually undergo change. 

 Distil a mixture of water, salt, and ink ; examine residue and distillate. 



Third year {ahout 13 to 14 years of age). 



Repeat the experiments of drying and burning animal and vegetable foodstuffs 

 quarititatively. Completely dry (without burning) weighed quantities of finely 

 divided fat and lean meat, bread, and potato ; find percentage loss of moisture. 

 Heat weighed quantities of the dried foodstuffs on a crucible lid until all carbon 

 has burnt away and a mineral ash only is left. Find the percentage of ash in the 

 food-materials. Refer to loss of weight during roasting and baking ; the water 



