142 



" Vapor Index," its interpreter, if properly used 

 and their suggestions regarded, therefore, become 

 fuel-f^aving as well as health-co>iserviiig imtvamenta. 



The Barometer, mercurial or aneroid, is esteemed 

 by many as a valuable foreteller of changes of the 

 weather. Its fluctuations are, however, but there- 

 suits of changing pressure of the atmosphere at 

 points more or less remote. These variations may 

 not be attended by any change in the weather at the 

 place of observation ; and barometric indications of 

 promised rain, &fi., are often at fault, and the in- 

 strument has been condemned as unreliable. If, 

 however, the fluctuations of the mercurial column 

 be studied in connection with the Psychrometer, the 

 causes of uncertainty will be, in great measure, ob- 

 viated. No set of rules can be framed for universal 

 application, as each district has its peculiar condi- 

 titions ; but one simple rule will be found of very 

 general practical value as an aid in foretelling rain 

 or snow: A slow, stea'ly rise in the barometer, fol- 

 lowed by a fall, if accompunied hij an atmosphere 

 saturated with hmnidit)/^ wind and clouds favoring, 

 will be general!} followed by rain, if the tempera- 

 ture be moderate, — by snow, if near the freezing 

 point. A rise of the barometer and subsequent fall 

 will not be followed by snow or rain, though the 

 wind and clouds favor, if the relatloe-hnmiditij he 

 much below saturation. The Psychrometer thus 

 becomes an important adjunct to the barometer, and 

 without which, indeed, the latter insrument will 

 oftentimes lead to erroneous inferences. 



Resume. — The Psychrometer and "Vapor Index" 

 wdll enable any one to determine readily the propor- 

 tion of moisture in the external air or in that of a 

 living room, the sick room or other apartment. 

 Their intelligent use will render comfortable and 

 wholesome, rooms which are often over-heated 

 and pestilential from inattention to their indica- 

 tions. 



They will guide the nurse or physician to a better 

 knowledge of the conditions which surround the in- 

 valid, and enable them to adapt these to his wants. 

 They will enable the physician to sustain an artificial 

 climate, or more properly, a really natural climate, 

 in the hospital, or sick room wherein lung com- 

 plaints, &c., may be more readily and successfully 

 treated. 



Their application to the school room, the lecture 

 room and places of worship, will aid in preventing 

 the mental dullness and stupor which affect pupils 

 and an audience in rooms heated by comparatively 

 dry air. 



They will supply the horticulturist with instru- 

 ments by which he may readily determine the actual 



state of the air surrounding his plants : and will en- 

 able the amateur florist to provide in her dwelling 

 room the conditions of moisture necessary for healthy 

 plant growth. 



Finally, if used according to the directions, and 

 the requisite supply of moisture be sustained, they 

 will, by inducing a wholesome, semi-humid state of 

 the air of apartments, enable the occupants to enjoy 

 a greater degree of comfort, at a moderate temper- 

 ature, than they have ever done at a higher one, 

 and thereby may contribute to economy in fuel to an 

 appreciable degree. 



VINEGAR PROM THB SUGAR MAPLE. 



BY J. H. HOLDING, HAMMONTON, N. J. 



I find a Washington correspondent asking if vin- 

 egar can be made from Maple sap. I reply in the 

 affirmative. When I was up at, or near, Sci anton, 

 Pa., I made some, for two seasons, that I and others 

 liked better than the best cider vinegar. The way 

 I found it out was this : I was out on the mountains 

 a little distance back from the town, (on mo.e of a 

 botanizing tour than any thing else,) I came across 

 a party in the sap bush having, as they termed, a 

 good time eating maple sugar. They very kindly 

 invited me to join them: I accepted the offer, by 

 tasting some of their partially condensed sap. A 

 thought struck me at once that I could make an ar- 

 ticle I have longed for ever since I left Old England. 

 That was a good drop of table beer. 



There being plenty of maples just back of my 

 place, I went right into it, and made several barrels. 

 It made beer more pleasant to my palate than any 

 I ever tasted in America. In setting them away in 

 the cellar, from some neglect, one cask got left with- 

 out bunging.. We emptied the first cask about the 

 1st of June, and on tapping the second, we found it 

 tolerably good vinegar, but not quite sour enough. 

 I divided it into 2 casks and put I gallon of vinegar 

 into one cask, and nothing in the other, and set them 

 both out in the sun, covering them with gauze to 

 keep out insects. 



In two weeks, the cask to which I added the vin- 

 egar, was sour enough for anything": the cask to 

 which nothing was added but sour beer, made the 

 best vinegar in the end, but it was longer before it 

 was ready for use, — but much the best flavor of the 

 two. The next season, I made some the same as 

 for beer, but let it assume the Acetic fermentation, 

 and we had the sour vinegar, for family use, for 3 

 years. I reduced some sap as for beer, but omitting 

 che hops, it did not make a good article. We put 

 down pickles in maple sap vinegar that kept better 

 than in cider vinegar. 



