A guide to the scientific knowledge of things familiar / by the Rev. Dr. Brewer.
- E. Cobham Brewer
- Date:
- [1853]
Licence: Public Domain Mark
Credit: A guide to the scientific knowledge of things familiar / by the Rev. Dr. Brewer. Source: Wellcome Collection.
46/496 page 34
![Q. How can ] 140 of heat be added to water, without being perceptibJe to our feelings ? A. 1st—140° of heat are hidden in water, when ice is melted by the sun or fire: and Sndly—1000° more are secreted, when water is converted into steam. Thus, before ice is converted into steam, 1140° of heat become latent. One pintof boiling water, (212° according to the thermometer) will make 1800 pints of steam; but the steam is no hotter to the touch than boiling water, both are 212°; therefore, when water is converted into steam, lOOOo of heat become latent. Hence, before ice is converted into sieam, it must absorb 1140° of latent heat. Q. How can we be made to feel the heat of ICE or snoio p A. Into a pint of snow put half as much salt; then plunge your hands into the hquid; and it will feel so intensely cold, that the snow itself will seem ivarm in comparison to it. Q. Is SALT and snow really colder than snow ? A. Yes, many degrees ; and by dip- ping your hand into the mixture first, and into snow aftenvards, the snow will seem to be comparatively warm.](https://iiif.wellcomecollection.org/image/b21495464_0046.jp2/full/800%2C/0/default.jpg)
