312 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



LOCTOBEB, 



temperature remaining the same, that portion of the elastic force 

 p, which depeuJs on the air alone, wliieh occupies the space n', 

 n 



lA P X -,; 



and this, together with E, must make up the atmosplierio pressure. 

 Or, p = px-, + E; 



whence, n' 



1 — 



= 1-01013, as before. 



E -Mi 



'p 30 



In the Greenwich Meteorological Observations will be found a 

 table calculated from this formula, for every degree, from 0"' to 9U\ 

 From the introduction to the yearly volumes, the following formulae 

 and explanations are extracted: — 



'■Gay-Lussac has determined by experiment, that vapours, so long 

 as they remain in an aeriform state, expand by the increa?e of tem- 

 perature, precisely as permanently elastic fluids, and that they 

 feiift'er changes of volume proportional to tlie changes of pressure; 

 and he has, as previously stated, determined that air expands ^ of 

 its bulk from 32= to 212°, and that its expansion is uniform 

 between these points. 



Therefore, if the weight of a cubic foot of vapour, under the 

 pressure of 30 inches of mercury, and at the temperature of 212', 

 be called W, and the weight — expressed in tlie same denomination 

 — -of an equal volu'ne of vapour at the temi)erature t, be called 

 W", and, if E; be the elasticity of vapour at the temperature t, 

 tlien (the expansion of dry air from 32° to 212° being 0-375, or 

 I'eiug ^Jffth part, equals 0-002083 for each degree of temperature), 

 ^y, _ 1-375 X W X Et 



30 (1 + -002083 . «°~^^32)" 



Now, Gay-Lussac has also determined that a cubic inch of vapour, 

 at 212% weighs 0-U9176 grains under the pressure of 29-922 inches 

 of mercury; and, consequently, a cubic foot of vapour, under the 

 same circumstances, weighs 0-H9176 -|- 1728 = 257-776 grains; 

 and under a pressure of 30 inches, it weighs 



30 

 o + 257-776 grains = 258-448 grains. 



Therefore, substituting this weight for AV, the formula becomes 



1-378 X 258-448 X Et 



W = ~ - ; 



30 (1 + -002083 X t° — 32°) 



and from this formula may be formed a table, showing the weight 

 of a cubic foot of vapour in grains, under the pressure of 30 inches 

 of mercury for any range of the thermometer. 



The degree of humidity shows, on a natural scale, the condition 

 of the air as regards moisture; complete saturation being repre- 

 sented by unity, and the air absolutely deprived of moisture by 

 zero. The numbers are obtained by dividing the quantity of 

 vapour which tlie air contained at the time of observation, by the 

 quantity which it would contain if it were in a state of complete 

 sat\iration." 



From these principles, combined with an extension of the calcu- 

 lations which I have not thought fit to enter upon, JMr. Glaisher 

 lias formed his hygrometrical tables, entering which with simply 

 llie readings of the dry and wet bulb thermometer, we are enabled 

 to obtain by inspection — 



1. The temperature of the dew point. 



2. The elastic force of vapour in inches of mercury. 



3. The weight of vapour in a cubic foot of air. 



4. The weight of vapour required for saturation of a cubic foot 

 of air. 



5. The degree of humidity. 



6. The weight in grains of a cubic foot of air. 



( To be continued.J 



YORKSHIRE AGRICULTURAL & COMMERCIAL BANK. 



AVe lately gave an engi-aving of a bank erected by ^lessrs. 

 Atkinson, at AV^hitby; and in noticing another bank by "them, we 

 shall have occasion to make similar remarks. The' bank now 

 shown to our readers, is the office, at York, of the Yorkshire Agri- 

 cultural and Commercial Banking Company. It is situated at "the 

 corner of High Ousegate and Castlegate, 'occupying an irregular 

 plot of ground, but having a straight front towards High Ouse- 



gate. The style adopted is Italian, with a good cornice, and with 

 rustications on the base. The height is in three stories, with a 

 basement, being altogether about 60 feet above the level of the 

 pavement. On the Castlegate side, which is of some length, it 

 has been necessary to make the building on two lines receding 

 from tiie main front. ' 



^L 





PLAN OF GHOUND PLOCB. 



The ground-floor, which contains the hanking oflSces, is of a 

 height of 18 feet, and has an entrance, and two windows with 

 circular heads. The material used is rubbed or cleansed Park- 

 spring stone, rusticated in the quoins, and with abase rusticated in 

 panels, and, except where interrupted by doorways, carried around 

 the building. The first floor is 13 feet high, and has three windows 

 in front, ornamented with mouldings, brackets, and carving. On 

 the Castlegate side are six windows. 



By the internal arrangements the whole front of the ground- 

 floor is appropriated as the banking office, making a room 27 feet 

 by 24 feet, and 18 feet high. Behind this are the manager's room, 

 director's room, and manager's parlour. The banking office is 

 highly enriched and well fitted. The windows have Bunnett 

 and Corpe's iron revolving shutters. The basement is made fire- 

 proof, and contains two fire-proofrooms. Into one of these works 

 a large iron safe, like that described for the Whitby Bank. It is 

 under the front counter in banking hours, and descends into the 

 vault by an hydraulic pump. A wrought-iron door closes this 

 vault when the safe is down. The safe contains all the cash- 

 drawers, and was provided by Dewer and Co., at a cost of 200/. 

 The cost of the building, exclusive of counters and furniture, was 

 nearly 4000/. The fire-proof vaults communicate with the bank 

 abo^'e by a stair, and are shut off from the manager's private 

 residence and offices. 



