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-■— ' CHESTER. MOLD, DENBIGH.…

RHYL, ST. ASAPH, AND DENBIGH.

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%- IT r -fc ^"-n >.rr, SCIENCE…

WHY RUBBER TYRES GET HOT.

AN EYE EXHIBITION.

DENATURED ALCOHOL.

MICROPHONE FIREDAMP DETECTIVE.

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MICROPHONE FIREDAMP DETECTIVE. In France Monsieur Hardy has invented an application of the microphone to detect firedamp in mines. This is its principle: If eound-wavee from two pipes of equal pitch impinge on .microphones connected in series with a telephone, a clear note is heard; but if one of the pipes emits a slightly different note, beats will be heard in the telephone. Here is the application: One pipe is placed in the mine, the other above ground, and they are blown simultaneously. If the air in the mine is charged with firedamp, it will produce a different note from that produced by clear air, owing to the difference of den- sity, and, in consequence, a series of beats in the telephone gives warning of the pre: sence of firedamp. The same apparatus is very sensitive to the presence of coal-gas.

WALL-PAPER AND TEMPERAMENT.

TO HELP THE VOICE.

CONCRETE AND STEEL.

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HINTS FOR THE HOME.

I LABOUR - SAVERS.

SLEEPING ALONE.

HOME LIFE. i

'CARE OF BOOTS.

EATING THE 'CRUSTS.

TO BRIGHTEN COLOURS.

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|Cricket.

LLANYCHAN AND DISTRICT CRICKET…

VALE OF CLWYD CRICKET CLUB.

VALE OF CLWYD v. FIELDFARES.

COUNTY CRICKET.

- LLANYCHAN v. MOSTYN PARK.…

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Sanitation at St Asaph. ..