Google reported continual strong results, but still fell below Wall Street expectations, sending the company’s stock falling after hours.

    Net income for the second quarter of 2007 was $925 million, up 28 percent from $721 million in the same period last year. However, it was down from $1 billion for the first quarter of 2007.

    Profit was $3.56 per share, below a Bloomberg survey of analysts’ expectations of $3.57 per share and a Thomson survey expecting $3.59 per share.

    This was only the second time in Google’s 12 public quarters that the company has missed estimates. The last time was in January 2006.

    Gross revenues were $3.87 billion for the second quarter 2007, a 58 percent increase over the same period last year but just a 6 percent increase over the first quarter of 2007.

    In explaining the earnings, Google CEO Eric Schmidt said the company had incurred higher expenses because it had hired more employees than it had expected to, and also spent considerable funds on investment in technology.

    The company added 1,548 employees in the quarter, for a total of 13,786, a 74 percent increase over the past year.

    Mr.Schmidt also touted the company’s continued revenue growth and increased web site traffic. “We’re very pleased with what we’re delivering,” he said in a conference call with analysts.

    Google-owned sites generated much stronger revenues in the second quarter—$2.49 billion—than its affiliate partner sites, which brought in $1.35 billion through the company’s AdSense advertising program. Revenue from Google-owned sites jumped 74 percent compared with the same period last year, while the partner sites jumped a more modest 36 percent over last year. Google has much more control over the quality of its own sites, to limit click fraud, for example.