Engine Manufactory
New Road
March 20th [1838]
Sir
We have inspected the Steam Engine & Machinery at the Zoological Gardens and we beg to submit for consideration of the Council the following remarks
Our information is
"That the last years expences including some repairs was £241.67"
"That the quantity of water raised was 180 Tons weight per Diem"
"That the average quantity of Coal consumed per hour was 112lbs and an additional 140 lbs used daily in getting up the Steam"
"That the cost of Welsh Coal was £1. 11. 8 1/2 per Ton"
"That the time of working the Engine is Four hours per day in Winter and eight hours per day in Summer say an average of 6 hours
"That the cylinders of the Pumps are 5 inches in diameter, 13 inches length of stroke and taking 18 strokes per minute"
Now upon a calculation we have made from the data given us we can make neither the quantity of water raised, not the annual amount of expence agreed. In the first place three 5 inch cylinders 13 inch strokes taking 18 strokes per minute in a proper states of repair would only deliver from 2600 to 2700 gallons of water per hour, and this quantity say for 6 hours would be equal to 16200 Gallons being only Seventy-two Tons - six cwt (Tons 72 6cwt) per day instead of 180 Tons of water as stated showing a discrepancy of nearly 108 tons of water per day.
Secondly as to expence we proceed thus -
Coal consumed per week of 6 days averaging
6 hours each day 43 1/2 cwt £3. 8. 9
Labor 1.10.-
Tow, Hemp, Tallow & Sundries - 15. -
Total for week £5.13.9
Making an Annual outlay of £294.4.8
Without any essential repairs - wear & tear, interest of Capitol etc. We are of opinion that an outlay of from £50 to 70 would complete the repairs at present necessary to the Engine and Pumps & the resetting of the Boiler. We should be happy to do the repairs of the present Machinery when occasion requires but we would rather decline entering into any specific contract - Although we decline entering into any contract retaining the present Machinery we have no objection to enter into an engagement for the supply of water to the gardens upon the following terms - To take away the present Engine, and Boiler and such other parts of the Machinery as we dee, necessary, to replace the same with an Engine and Boiler of sufficient power to supply the present quantity of water, and to take upon ourselves the expence of all repairs, Engine fuel etc etc for a term of Three Years for a sum of Three Hundred pounds per Annum payable quarterly in advance On the expiration of the Three years, if the contract be not renewed, the Engine and Boiler placed by us to be taken by the Council at a fair valuation. It must be clearly understood that we cannot guarantee the supply of Water in the Well
Waiting your further commands
We remain Sir
Your obedient Servants
Braithwaite, Milner & Co
To the Revd Barlow