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THE GARDENERS' MONTHLY 



[April, 



sessing more or less considerable area of glass 

 heated by the hot-water system, had not unnatu- 

 rally led a few into an opposite error, 'that is, to 

 attempt to utilize the existing pipe (4-inch cast iron) 

 to convey the steam therein. In the case of the 

 ordinary soil pipe, generally used for hot water, I 

 do not hesitate to state most emphatically that they 

 are useless for steam, no matter at how low a press- 

 ure. I have admitted steam to a line of them at 

 less than half-pound pressure, and had upward of 

 100 feet of them cracked in an instant. The much 

 heavier pipe made by some manufacturers (Messrs. 

 Hitchings & Co., for instance), may be able to 

 carry steam at low pressure ; but I should hesitate 

 about assuming so great a risk ; and why should 

 you do so when there are several ways out of the 

 difficulty ? In the first place, by taking your pipe 

 apart, you may realize, as has been done here, to 

 my knowledge, almost if not quite sufficient to pay 

 for a complete outfit of steam apparatus. Should 

 your pipe, however, be joined with iron filings, and 

 therefore too troublesome to take apart, I should 

 advise the adoption of the method described by 

 Messrs. R. G. Parker & Co., of Boston (Sept. No. 

 G. M., 1880), that is, to heat the water in your 

 pipes by steam through a coil introduced in place 

 of your respective hot water boilers. You will 

 thereby enjoy nearly all the advantages of the 

 steam system, and may of course use direct steam- 

 heating apparatus in any additional houses, while 

 firing the entire establishment from one point. 



To mention a few other points suggested through 

 the correspondence arising on the subject, and 

 which I shall touch as briefly as possible : Capacity 

 of boiler in horse powers. From my experience 1 

 should advise one-horse power for each 120 square 

 feet of radiating surface, which in two-inch pipe is 

 about 240 lineal feet ; but I consider liberality on 

 that point a wise economy. Another point of ad- 

 vice is to rather use two boilers placed in battery, 

 but in such a way as to be able to use but one at a 

 time or both together, as circumstances require. 

 Be sure to provide both ample steam and water 

 connection (4-inch or more), for reasons it would 

 take too long to explain, but is nevertheless of 

 greatest importance. 



The advantage of being able to return the con- 

 densation to the boiler is so great, not only regarded 

 from the standpoint of economy in fuel, that I ven- 

 ture to allude to it again ; much the same as Mr. 

 Peter Henderson, referring so frequently to the im- 

 portance of firming the soil about seeds because of 

 its great importance. In addition to effecting a 

 most decided economy in fuel, it insures freedom 



from scale or mud deposits in the boiler, because 

 the same water is used over and over again. It 

 also insures you from the danger arising from a 

 sudden stoppage of your water supply, caused by 

 freezing, or perhaps a break in the water pipe which 

 supplies you, and which would leave your boiler 

 dry before you could devise any means to prevent 

 such a mishap; in short, my urgent advice is, not 

 to neglect this point above all others. I regard all 

 other devices for the better control of steam as a 

 heating medium, highly valuable as some of them 

 undoubtedly are, as secondary to the absolute and 

 constant return of the condensation to the boiler. 

 Of these above devices I would mention as very 

 desirable a good damper-regulator ; its name suffi- 

 ciently describes its use ; also a reliable pressure- 

 regulating valve, which will keep the steam in 

 your heating pipes at any uniform pressure you 

 may want (thus guarding against overheating 

 through carelessness) as long as you maintain 

 as much or more pressure in your boiler. 



Such safety-guards are not only of great assist- 

 ance in the uniformly even performance of the en- 

 tire apparatus, but they also effect a very notice- 

 able saving in fuel. 



I believe this covers the principal points of the 

 inquiries I have had on the subject. I have tried 

 to avoid the use of technical terms as much as 

 possible, so as to be intelligible to those of your 

 readers not mechanics enough to grasp their 

 meaning. If I have succeeded in making myself 

 understood I shall feel amply paid for the effort. 



BLISTERED LEAVES IN GREENHOUSE 

 PLANTS. 



BY G. GEDULDIG, NORWICH, CONN. 



It seems that most florists and gardeners do not 

 know how plants get burnt through the sun. Mr. 

 Peter Henderson, even, advises in his pamphlet, 

 "Greenhouse Structures," to throw away all glass 

 having flaws, etc. I never found burnt leaves 

 from such glass. All burns I found to come when 

 water lodges between the laps, which will make a 

 focus when the sun strikes it on the right angle. 

 Such panes of glass do not lay tight enough on 

 each other, hence the blistering water is held 

 there. Such laps should be filled with putty. 



[Mr. Geduldig is probably correct in his judg- 

 ment. The writer of this has hitherto believed 

 with Mr. Henderson and others, that some defect 

 in the glass has caused the blistering ; yet he has 

 often endeavored to trace the relation between 

 these burnt leaves with the ideal "blister in the 



