Expanding liquid thermometer comprising: a / a reservoir of thermometric liquid, b / a capillary tube in fluid communication with said reservoir of liquid, comprising a first end and a second end, c / a tubular casing of transparent material comprising: - an outer surface, - an inner surface delimiting an inner volume, - a first casing end, - a second envelope end which comprises a closing wall closing off said internal volume, and which comprises an internal surface formed from a portion of said internal surface of said tubular casing, at the level of which second casing end is formed said liquid reservoir, and in the internal volume of which tubular casing extends said capillary tube, and d / a graduated scale facing at least part of said capillary tube, said liquid reservoir being formed integrally with said first end of said capillary tube, said liquid reservoir comprising an outer surface which extends opposite said internal surface of said second end of the tubular casing, said thermometer comprising securing means between said internal surface of said second end of the tubular casing, on the one hand, and said outer surface of said liquid reservoir, on the other hand, characterized in that said securing means consist of a silicone type adhesive. a / a reservoir of thermometric liquid, b / a capillary tube in fluid communication with said reservoir of liquid, comprising a first end and a second end, c / a tubular casing of transparent material comprising: - an outer surface, - an inner surface delimiting an inner volume, - a first casing end, - a second envelope end which comprises a closing wall closing off said internal volume, and which comprises an internal surface formed from a portion of said internal surface of said tubular casing, at the level of which second casing end is formed said liquid reservoir, and in the internal volume of which tubular casing extends said capillary tube, and - an outer surface, - an inner surface delimiting an inner volume, - a first casing end, - a second envelope end which comprises a closing wall closing off said internal volume, and which comprises an internal surface formed from a portion of said internal surface of said tubular casing, d / a graduated scale facing at least part of said capillary tube, said liquid reservoir being formed integrally with said first end of said capillary tube, said liquid reservoir comprising an outer surface which extends opposite said internal surface of said second end of the tubular casing, said thermometer comprising securing means between said internal surface of said second end of the tubular casing, on the one hand, and said outer surface of said liquid reservoir, on the other hand, characterized in that said securing means consist of a silicone type adhesive. said liquid reservoir comprising an outer surface which extends opposite said internal surface of said second end of the tubular casing, said thermometer comprising securing means between said internal surface of said second end of the tubular casing, on the one hand, and said outer surface of said liquid reservoir, on the other hand, characterized in that said securing means consist of a silicone type adhesive.